tag:theconversation.com,2011:/us/topics/forensic-evidence-6059/articlesForensic evidence – The Conversation2023-11-08T06:45:09Ztag:theconversation.com,2011:article/2006352023-11-08T06:45:09Z2023-11-08T06:45:09ZThe words that helped wrongly convict Kathleen Folbigg<blockquote>
<p><strong>Prosecutor:</strong> Are you able to say whether or not Caleb died from a catastrophic asphyxiating event of unknown causes? </p>
<p><strong>Pathologist:</strong> I believe that is likely. […]</p>
<p><strong>Prosecutor:</strong> In relation to Laura […] her cause of death was consistent with smothering? </p>
<p><strong>Pathologist:</strong> Yes.</p>
<p><strong>Prosecutor:</strong> Including deliberate smothering?</p>
<p><strong>Pathologist:</strong> Yes.</p>
<p><strong>Prosecutor:</strong> And that she probably died from an acute catastrophic asphyxiating event of unknown causes?</p>
<p><strong>Pathologist:</strong> Yes. – (<a href="https://www.folbigginquiry.justice.nsw.gov.au/Documents/Amended%20Exhibit%20F.pdf">Transcript pp. 746-48</a>)</p>
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<p>The above exchange occurred during the seven-week trial leading to Kathleen Folbigg’s conviction for the deaths of her four infant children (Caleb, Patrick, Sarah and Laura) between 1989 and 1999. During the trial, the word “asphyxia” in its various forms (-ate; -ation; -ating) was used 208 times; “smother” (-ing; -ed) 221 times; and “consistent with” 233 times. </p>
<p>The pathologists and doctors concurred that the absence of external injuries was “consistent with” Caleb dying of a “catastrophic asphyxiating event”. This was repeated for each of the four children by each of the doctors, with strangling or smothering likely to be uppermost in the minds of the jurors. </p>
<p>Of course, Folbigg’s wrongful conviction had <a href="https://johnmenadue.com/the-wrongful-conviction-of-kathleen-folbigg-why-did-it-happen-and-what-must-be-done-to-stop-it-from-happening-again/">numerous factors</a>. We have no way of knowing why the jury decided as it did. </p>
<p>But there are good reasons for forensic medicine practitioners and advocates to rethink their understanding – and use – of these words. </p>
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<h2>The semantic journey of asphyxia</h2>
<p>“Asphyxia” first appeared <a href="https://quod.lib.umich.edu/cgi/t/text/text-idx?c=eebo2;idno=B22610.0001.001">in print</a> in 1699 defined as “without any Pulse, or sign of Life”. Predictably, this meaning “stoppage of pulse” then sprouted the meaning “stoppage of respiration” – a lack of breath is a salient sign of lifelessness. </p>
<p>Subsequently, the path has been rocky, and it is now understood variously by forensic doctors around the world. What is agreed, however, is that “asphyxia” is not a diagnosis; it is not a condition that can be pointed at or diagnosed. </p>
<p>As far as lay understandings go, things get murkier. Modern dictionaries list many senses but privilege “respiratory failure”, with “suffocation” usually given as a synonym; this in turn is defined as the interruption of breathing, including some means by which it’s brought about (for example, smothering, throttling). </p>
<p>The Urban Dictionary’s definition for “asphyxiation” is “death by strangulation; ergo blockage in air passage”. This dictionary has its problems, but like other collaboratively constructed dictionaries, it is useful for tracking contemporary social meanings of expressions not yet in more mainstream dictionaries.</p>
<h2>More murkiness</h2>
<p>In the trial, confused senses of “asphyxia” were combined with the misleading phrase “consistent with”. As used by experts, this is synonymous with “may or may not mean”. </p>
<p><a href="https://repository.uclawsf.edu/hastings_law_journal/vol59/iss5/7/">Research</a> shows, however, that people without expert knowledge hear the phrase as strong confirmation of the proposed connection.</p>
<p>In the <a href="http://netk.net.au/Canada/Morin10.asp">1998 Canadian inquiry</a> into the (wrongful) conviction of Canadian man Guy Paul Morin, Commissioner Kaufman was scathing in his criticism of the use of “consistent with”. He regarded it as demonstrably misleading language, variably being used to mean:</p>
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<p>‘could have come, or cannot be excluded as coming, from the accused’; ‘not inconsistent with’; ‘more than a possibility but less than a probability’; ‘perfect or near identity of two items’.</p>
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<p>The <a href="https://www.oed.com/dictionary/consistent_adj?tab=meaning_and_use">historical thesaurus</a> of the Oxford English Dictionary suggests this last sense “perfect or near identity of two items” has been around since the 1600s. Clearly, we can’t assume people today would automatically understand “consistent with” as simply a way of saying what is proposed is possible.</p>
<h2>Bad meanings drive out good</h2>
<p>The meanings we carry around in our heads seem so natural we fail to realise other people can have quite different understandings. </p>
<p>As linguist <a href="https://oxford.universitypressscholarship.com/view/10.1093/acprof:oso/9780198709831.001.0001/acprof-9780198709831">Nick Enfield</a> describes, we hypothesise what others mean by the words they use. And the more unusual a word is, the more its meanings will vary because we aren’t given the same opportunities to refine our hypotheses. </p>
<p>For example, what part of the foot do you understand as the “instep” – the upper surface between toes and ankle, the underneath part, or perhaps both the top and underneath? All three meanings are out there, and different dictionaries favour different ones. </p>
<p>Does this really matter? In a highly circumstantial murder trial, it does.</p>
<p>Words are <a href="https://www.cambridge.org/core/books/forbidden-words/E7E4C037E8F1A91DE2ECA05CD70A3078">far more likely</a> to take on negative overtones than favourable ones. The linguistic evidence is compelling – negative senses come to dominate and eventually quash all other senses. This transformation has a name: Gresham’s Law of Semantic Change.</p>
<p>It comes as no surprise that crowdsourced online dictionaries show the homicidal senses of “asphyxia” (and its derived forms) as winning out.</p>
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<h2>Asphyxia permeated Kathleen Folbigg’s trial</h2>
<p>Importantly, it was agreed by all involved none of the babies showed any injuries. (Two pinpoint scratches on Sarah’s lower lip were agreed to be of no significance).<br>
As the prosecutor said: </p>
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<p>All they [the doctors] can say is that there was some form of obstruction that caused oxygen not to be able to get into the lungs and that’s what caused these babies to die […] all they can say is that it was induced asphyxiation from an external cause […]“ (<a href="https://www.folbigginquiry.justice.nsw.gov.au/Documents/Amended%20Exhibit%20F.pdf">Transcript p. 66</a>)_</p>
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<p>It was repeatedly asserted the presence of no injuries in any of the Folbigg children "was consistent with the occurrence of an acute catastrophic asphyxiating event” or “smothering”. This was probably heard by the jury as indicating no injuries meant an “asphyxial event” had occurred – in other words, the children had been strangled or smothered. </p>
<p>There was also repeated reference to the absence of natural explanations for four sudden and unexplained deaths in one family – with the unstated inference that the only reasonable explanation was homicide. Known as Meadows Law, this inference stalked Kathleen Folbigg’s trial and her subsequent appeals relentlessly. Meadows Law falls at the first hurdle: how likely is it there would be four murders – where there are no injuries – masquerading as natural deaths? </p>
<p>In <a href="https://www.austlii.edu.au/cgi-bin/viewdoc/au/cases/nsw/NSWSC/2003/895.html?context=1;query=R%20v%20Folbigg;mask_path=au/cases/nsw/NSWSC">his sentencing remarks</a>, the judge stated:</p>
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<p>No (expert) witness was prepared to say that the signs pointed only to smothering but the medical evidence generally was that the result of each event was consistent with having been caused by acute asphyxiation. The jury accepted that evidence.</p>
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<p>That summary encompasses the following linguistic storm: the doctors might say they thought the prosecutor was talking about asphyxia as meaning hypoxia/anoxia (low oxygen levels) due to any one of a myriad of causes.</p>
<p>The prosecutor believed he was asking whether, and the doctors were telling him that, the babies died from induced airways obstruction from external causes. And the jury thought they were being told the babies were smothered, or even strangled.<br>
All of this is medically incoherent and incapable of establishing anything of significance – but probably had a powerful effect on the jury. </p>
<h2>'The wisdom of the crowd’</h2>
<p>Since its first appearance in English in the 1600s, the term “asphyxia” has caused confusion. </p>
<p>In forensic pathology, it encompasses a number of concepts and is used variously by pathologists – and these uses are out of alignment with common lay usage. Combined with different understandings of “consistent with”, this confusion was very much to Folbigg’s disadvantage. </p>
<p>The jury system relies on “the wisdom of the crowd”. Forensic doctors, advocates and judges must recognise that, despite what they think and dictionaries say, the crowd can understand words very differently, and this can have consequences. </p>
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Read more:
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<p class="fine-print"><em><span>Professor Cordner was an expert witness at both Commissions of Inquiry into the convictions of Kathleen Folbigg. </span></em></p><p class="fine-print"><em><span>Kate Burridge does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The meanings we carry around in our heads seem so natural and inborn that we fail to realise other people can have quite different understandings.Kate Burridge, Professor of Linguistics, Monash UniversityStephen Cordner, Senior Consultant/Professor Emeritus, Dept of Forensic Medicine, Monash University, Victorian Institute of Forensic MedicineLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2108362023-09-28T12:28:47Z2023-09-28T12:28:47ZJuries that don’t understand forensic science can send innocent people to prison − a short training video could help<figure><img src="https://images.theconversation.com/files/550656/original/file-20230927-21-d5p74f.jpg?ixlib=rb-1.1.0&rect=928%2C0%2C7011%2C4916&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Jurors tend to rely heavily on forensic testimony, even when they don't understand it.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/witness-addressing-the-courtroom-in-a-trial-royalty-free-image/844393098">andresr/E+ via Getty Images</a></span></figcaption></figure><p><a href="https://www.law.umich.edu/special/exoneration/Pages/casedetail.aspx?caseid=5159">Ledura Watkins</a> was 19 years old when he was accused of murdering a public school teacher. At trial, a forensic expert testified that a single hair found at the scene was similar to Watkins’ and stated his conclusion was based on “reasonable scientific certainty.” He explained that he’d conducted thousands of hair analyses and “had never been wrong.”</p>
<p>This one hair was the only physical evidence tying Watkins to the crime. In 1976, Ledura Watkins was convicted of first-degree murder and sentenced to life in prison without the possibility of parole.</p>
<p>Here’s the catch: The expert’s testimony was inappropriate and misleading, and the jury made a mistake. Watkins was innocent. Ledura Watkins lost over 41 years of his life to a <a href="https://www.law.umich.edu/special/exoneration/Pages/casedetail.aspx?caseid=5159">wrongful conviction based on improper forensic testimony</a>.</p>
<p><a href="https://scholar.google.com/citations?user=wR9V8s8AAAAJ&hl=en&oi=sra">Our interdisciplinary</a> <a href="https://scholar.google.com/citations?user=syay8eEAAAAJ&hl=en&oi=ao">team of</a> <a href="https://scholar.google.com/citations?user=m9pMkQcAAAAJ&hl=en&oi=ao">legal psychologists</a>, <a href="https://gfjc.fiu.edu/">forensic experts</a> <a href="https://scholar.google.com/citations?user=STmVsAgAAAAJ&hl=en&oi=ao">and an attorney</a> worked to develop an educational tool to help jurors avoid making similar mistakes in the future.</p>
<h2>Forensic testimony carries weight with jurors</h2>
<p><a href="https://www.law.umich.edu/special/exoneration/Pages/ExonerationsContribFactorsByCrime.aspx">One out of every five wrongful convictions</a> cataloged through September 2023 by the <a href="https://www.law.umich.edu/special/exoneration/Pages/mission.aspx">National Registry of Exonerations</a> involved improper forensic evidence.</p>
<p>There is reason to be concerned about jurors’ ability to adequately evaluate forensic evidence. <a href="https://doi.org/10.1007/BF01498976">Jurors tend</a> <a href="https://doi.org/10.1111/j.1559-1816.1990.tb00400.x">to rely heavily</a> <a href="https://doi.org/10.1037/lhb0000423">on forensic evidence</a> <a href="https://doi.org/10.1037/1076-8971.14.1.27">when making decisions</a> in a case, <a href="https://doi.org/10.1023/A:1022368801333">despite struggling to</a> <a href="https://doi.org/10.1037/lhb0000027">understand the statistical analyses</a> <a href="https://doi.org/10.1086/428020">and language used</a> to explain forensic science. They might ignore the differences between appropriately worded forensic testimony <a href="https://doi.org/10.1037/lhb0000423">and testimony that violates best-practice guidelines</a>, fail to grasp the limitations of forensic science in expert witness testimony and <a href="https://doi.org/10.1007/s10979-008-9169-1">overly rely</a> <a href="https://doi.org/10.1037/law0000103">on an expert’s experience</a> when evaluating the evidence.</p>
<p>Despite all these issues, jurors remain <a href="https://doi.org/10.1007/s10979-008-9169-1">overconfident in their ability</a> to comprehend forensic testimony.</p>
<p>Researchers have long suggested that part of the problem is the <a href="https://doi.org/10.1037/lhb0000423">way forensic evidence is presented</a> in courtrooms. In response to <a href="https://www.jstor.org/stable/25475240">calls by scientists</a>, the U.S. Department of Justice approved the <a href="https://www.justice.gov/olp/uniform-language-testimony-and-reports">Uniform Language for Testimony and Reports</a> in 2018. These <a href="https://www.justice.gov/media/1072031/dl?inline">guidelines</a> aimed to lessen misleading statements in forensic testimony and outlined five statements forensic experts should not make. The expert in Ledura Watkins’ case made several of these statements, including claiming that his examination was perfect because of the number of examinations he had conducted.</p>
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<p>It’s understandable that jurors are swayed by an expert who uses terms like “error free,” “perfect” or “scientific certainty.” We are interested in finding ways to help people critically evaluate the forensic testimony they hear in court.</p>
<h2>An informational video for jurors</h2>
<p>Inspired by one court’s use of <a href="https://www.wawd.uscourts.gov/jury/unconscious-bias">videos to help train jurors</a> on relevant concepts, our team developed what we call the forensic science informational video. It’s about 4½ minutes long and focuses on latent print examinations, including fingerprints, footwear impressions and tire impressions.</p>
<p>In the FSI video, a narrator explains what a forensic expert is and how they might testify in court. The video describes how latent print examinations are conducted and what types of statements are appropriate – or not – for an expert to make in their testimony, based on the DOJ guidelines.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/fZJAlB9OgLA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Mock jurors watched this training video about forensic testimony.</span></figcaption>
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<p>In two different studies, we recruited jury-eligible adults to test whether our video had any effect on how jurors judged forensic testimony.</p>
<p>In our first study, some participants watched the FSI video and others didn’t. Participants who watched the FSI video were <a href="https://doi.org/10.1177/00938548231195112">more likely to give lower ratings to improper forensic testimony</a> and the forensic expert who gave it.</p>
<p>In our second study, we tested whether the video could help jurors <a href="https://doi.org/10.1037/lhb0000539">differentiate between low-quality and high-quality testimony</a> without creating a general distrust in forensic evidence. Participants watched a 45-minute mock trial video. Without training from the FSI video, participants rated both low- and high-quality forensic testimony highly. That is, they didn’t differentiate between testimony in which the expert violated three of the DOJ guidelines and testimony that followed the guidelines.</p>
<p>But participants who watched our informational video prior to the mock trial were more likely to differentiate between the low- and high-quality testimony, rating the expert giving low-quality testimony more poorly than the expert giving high-quality testimony.</p>
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<span class="caption">In-court instruction can provide everyday citizens with the knowledge they need to make good decisions.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/sign-detailing-instructions-for-jurors-lies-in-a-hallway-news-photo/57502325">Chip Somodevilla via Getty Images</a></span>
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<h2>Training helps jurors assess forensic testimony</h2>
<p>These findings suggest that our informational video helped mock jurors in two ways. Participants learned how to identify low-quality forensic testimony and how to adjust their evaluations of the expert and their testimony accordingly. Importantly, the video did not cause participants to distrust latent print evidence in general.</p>
<p>Our study is a promising first step in exploring ways to help jurors understand complex forensic testimony. A brief video like ours can provide standardized information about forensic experts and types of appropriate and inappropriate testimony to jurors across courts, much like similar <a href="https://www.wawd.uscourts.gov/jury/unconscious-bias">videos about implicit bias</a> already being used in some courts.</p>
<p>We believe a training video has the potential to be easily implemented as an educational tool to improve the quality of jurors’ decision-making. A better understanding of the distinction between proper and improper testimony would improve the justice system by helping jurors fulfill their roles as objective fact-finders – and hopefully prevent wrongful convictions like that of Ledura Watkins.</p><img src="https://counter.theconversation.com/content/210836/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Devon LaBat receives funding from the National Institute of Justice. </span></em></p><p class="fine-print"><em><span>Deborah Goldfarb receives funding from the National Institute of Justice. </span></em></p><p class="fine-print"><em><span>Jacqueline R. Evans receives funding from the National Institute of Justice. </span></em></p><p class="fine-print"><em><span>Nadja Schreiber Compo received funding from the National Institute of Justice.</span></em></p>Educating mock jurors about what kinds of statements are appropriate − or not − led to more critical assessments of forensic testimony and improved the quality of their decisions.Devon LaBat, Doctoral Candidate in Legal Psychology, Florida International UniversityDeborah Goldfarb, Assistant Professor of Psychology, Florida International UniversityJacqueline R. Evans, Associate Professor of Psychology, Florida International UniversityNadja Schreiber Compo, Professor of Psychology, Florida International UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2074182023-07-30T20:08:31Z2023-07-30T20:08:31ZSecrets wrapped in fabric: how our study of 100 decomposing piglet bodies will help solve criminal cases<figure><img src="https://images.theconversation.com/files/539908/original/file-20230728-23-ku5ia8.jpeg?ixlib=rb-1.1.0&rect=19%2C3%2C1274%2C857&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Photo by Stevie Ziogos</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Until the <a href="https://www.sciencedirect.com/science/article/pii/B9780081018729000042">late 19th century</a>, the success of criminal investigations largely hung on witness reports and (often extorted) confessions. A lack of scientific tools meant investigators needed advanced <a href="https://www.sciencedirect.com/topics/psychology/deductive-reasoning">deductive reasoning</a> abilities – and even then they’d often hit a dead end.</p>
<p>Today, investigations demand an interdisciplinary and <a href="https://link.springer.com/article/10.1007/s00414-022-02846-6">high-tech</a> approach, involving experts from diverse scientific disciplines. Stabbing investigations are particularly important, as fatal stabbings are the leading cause of homicide in countries with restricted access to firearms, including <a href="https://www.aic.gov.au/sites/default/files/2020-05/tbp045.pdf">Australia</a>.</p>
<p>Carefully interpreting <a href="https://theconversation.com/the-camera-never-lies-our-research-found-cctv-isnt-always-dependable-when-it-comes-to-murder-investigations-199828">CCTV footage</a> can be useful, but sometimes the crime scene won’t have surveillance cameras. The victim’s body may be discovered days, weeks, or months after the event. By then it may be partially consumed by insects – or rain may have washed away the blood stains, or potentially even the murder weapon.</p>
<p>In such a case, analysing damage to a <a href="https://www.ojp.gov/ncjrs/virtual-library/abstracts/comparing-alleged-weapon-damage-clothing-value-multiple-layers-and">victim’s clothing</a> can provide crucial insight. But how does clothing on a decomposing body react to environmental and biological factors?</p>
<p>This was our question as we conducted research using the decomposing bodies of more than 100 stillborn piglets. Our findings from this <a href="https://www.mdpi.com/2075-4450/14/7/618">first-of-its-kind experiment</a> could help investigators solve future (and past) crimes in which stabs, tears or other damages to clothing are in question.</p>
<h2>Pigs wrapped in fabric</h2>
<p><a href="https://www.sciencedirect.com/science/article/pii/S1355030618301680">Textile analysis</a> has a significant role in forensic investigation. Clothes can preserve crucial information about the events leading up to someone’s death. Evidence might come in the form of fibres under a victim’s fingernails, <a href="https://www.pnas.org/doi/10.1073/pnas.1917222117">tears in the clothing</a> resulting from movement or traction, or cuts and holes caused by weapons. </p>
<p>However, the decomposition process itself will also alter the fabric and existing damages. It may even introduce new damages that complicate the analysis.</p>
<p>To understand how clothing might change throughout this process, we conducted an experiment in the summer heat of Western Australia. We used more than 100 stillborn piglets (simulating human remains) wrapped in common fabrics including cotton, stretchy synthetic material, and a fabric blend. Some piglets were left unclothed as control samples.</p>
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<a href="https://images.theconversation.com/files/539902/original/file-20230728-25-grpb0x.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/539902/original/file-20230728-25-grpb0x.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/539902/original/file-20230728-25-grpb0x.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/539902/original/file-20230728-25-grpb0x.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/539902/original/file-20230728-25-grpb0x.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/539902/original/file-20230728-25-grpb0x.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/539902/original/file-20230728-25-grpb0x.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/539902/original/file-20230728-25-grpb0x.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The experiment was conducted at a facility in Western Australia.</span>
<span class="attribution"><a class="source" href="https://www.mdpi.com/2075-4450/14/7/618">Photo by Stevie Ziogos</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We intentionally inflicted cuts and tears on most of the fabrics, before leaving the carcasses to decompose naturally in a bushland environment until only bones remained. The bodies were shielded from <a href="https://pubmed.ncbi.nlm.nih.gov/20171028/">large scavengers</a>, but not from <a href="https://pubmed.ncbi.nlm.nih.gov/19836175/">carrion insects</a>. </p>
<p>While previous research has explored the impact <a href="https://pubmed.ncbi.nlm.nih.gov/21602003/">of clothing on decomposition</a>, we were focused on the other side of the coin: how do insects impact the fabric on a decomposing carcass? And in what ways could this jeopardise an investigation? </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/flies-maggots-and-methamphetamine-how-insects-can-reveal-drugs-and-poisons-at-crime-scenes-176981">Flies, maggots and methamphetamine: how insects can reveal drugs and poisons at crime scenes</a>
</strong>
</em>
</p>
<hr>
<h2>Exposed to natural elements</h2>
<p>It wasn’t long before the fabrics started to transform due to exposure to bacteria, fungi, insects and other environmental factors. </p>
<p>They changed in shape and texture, and became stretched as a result of the natural bloating of the carcasses. Less than a week after the carcasses were placed, new holes appeared in the fabric – especially in cotton – as the fibres broke down.</p>
<p>There were also chemical changes due to potential exposure to body fluids and the chemical products of bacteria and fungi.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/539897/original/file-20230728-27-48r2yd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/539897/original/file-20230728-27-48r2yd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/539897/original/file-20230728-27-48r2yd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/539897/original/file-20230728-27-48r2yd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/539897/original/file-20230728-27-48r2yd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/539897/original/file-20230728-27-48r2yd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/539897/original/file-20230728-27-48r2yd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/539897/original/file-20230728-27-48r2yd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Experimental fabrics observed with a ‘scanning electron microscope’ (SEM) showed fungal colonisation.</span>
<span class="attribution"><a class="source" href="https://www.mdpi.com/2075-4450/14/7/618">Photo by Stevie Ziogos</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Insects were particularly active in areas where body fluids were present. Of twenty insect groups collected and identified, blowflies and carrion beetles were the most common antagonists. </p>
<p>Throughout the 47 days of the experiment, we managed to collect a range of data on fabric degradation throughout the decomposition process. It’s the first time this has been documented in such detail in a controlled experiment. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/539893/original/file-20230728-19-9x88ao.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/539893/original/file-20230728-19-9x88ao.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/539893/original/file-20230728-19-9x88ao.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/539893/original/file-20230728-19-9x88ao.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/539893/original/file-20230728-19-9x88ao.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/539893/original/file-20230728-19-9x88ao.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/539893/original/file-20230728-19-9x88ao.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Insects visited the bloodstains of the fabric during the early stages of the experiment.</span>
<span class="attribution"><span class="source">Photo by Stevie Ziogos, Author provided</span></span>
</figcaption>
</figure>
<h2>New tools to solve new (and old) mysteries</h2>
<p>Although textile damage analysis is vital for forensics, there has been limited research on how it overlaps with forensic entomology and taphonomy (the study of how organisms decompose). Our research shows fabrics can hold significant evidence, and this evidence changes as bodies decompose while being exposed to the environment.</p>
<p>There are myriad examples of crimes where evidence related to clothing has been crucial to solving the case. </p>
<p>In the 1980 <a href="https://www.injustice.law/2021/07/05/the-shameful-tale-of-what-happened-to-lindy-chamberlain/">Chamberlain case</a>, a jury wrongly found Lindy Chamberlain and her husband Michael guilty of murdering their nine-week-old daughter Azaria, who had disappeared. </p>
<p>It was only when Azaria’s clothing was recovered a week after her disappearance that investigators had evidence of a dingo having snatched her (as the clothes showed signs of having been dragged through sand). The Chamberlains were exonerated as a result.</p>
<p>More recently, a person of interest was arrested in New York as the “<a href="https://7news.com.au/news/crime/architect-charged-over-murders-after-pizza-crust-leads-to-craigslist-ripper-breakthrough-c-11284691">Craigslist ripper</a>”, a serial killer responsible for the murder of more than ten people. Investigators obtained DNA evidence from strands of hair found in <a href="https://www.smh.com.au/world/hunt-for-ripper-as-new-york-beach-body-count-mounts-20111202-1obc7.html">burlap sacks</a> used to hide and transport the bodies. </p>
<p>Although many details of this particular case remain undisclosed, such investigations will most likely use insect-related evidence and other trace evidence on textiles to help make important inferences, including about time of death.</p>
<p>More generally, our work will help investigators avoid misinterpreting evidence from clothing. For instance, if investigators aren’t aware holes in fabric can form through exposure to insects and natural elements, they might incorrectly attribute them to an animal or human attacker. </p>
<p>Similarly, by gauging which portion of clothing has the most insect damage, they might be able to understand where the most fluid was present on the body (if it’s found as skeletal remains). This could help them figure out where and how damage was inflicted.</p>
<p>This year we published <a href="https://pubmed.ncbi.nlm.nih.gov/37367352/">guidelines</a> to help other forensic professionals in the process of observing and collecting insects at a crime scene, and in considering how insect activity may be connected with a victim’s clothing. We hope our work can help future investigations, and maybe even reopen some cold cases.</p><img src="https://counter.theconversation.com/content/207418/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This research has been conducted in collaboration with Stevie Ziogos (PhD candidate, Murdoch University) and Kari Pitts (ChemCentre). Forensic entomology guidelines have been updated in collaboration with Tharindu Bambaradeniya (PhD candidate, Murdoch University).</span></em></p><p class="fine-print"><em><span>Ian Dadour does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Fatal stabbings are the leading cause of homicide in countries with restricted access to firearms, including Australia. New research could help solve these cases.Paola A. Magni, Senior Lecturer in Forensic Science, Murdoch UniversityIan Dadour, Adjunct professor, Murdoch UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1807652022-04-07T14:20:53Z2022-04-07T14:20:53ZUkraine: how forensics teams will investigate evidence of atrocities at Bucha<p>Forensic investigators are <a href="https://www.ukrinform.net/rubric-ato/3450158-air-strikes-cluster-munitions-torture-russian-war-crimes-documented-in-bucha-and-borodianka.html">reportedly already at work in Bucha</a>, northwest of Kyiv, where grisly evidence has been found that could point to war crimes committed by Russian troops during their occupation of the area.</p>
<iframe id="noa-web-audio-player" style="border: none" src="https://embed-player.newsoveraudio.com/v4?key=x84olp&id=https://theconversation.com/ukraine-how-forensics-teams-will-investigate-evidence-of-atrocities-at-bucha-180765&bgColor=F5F5F5&color=D8352A&playColor=D8352A" width="100%" height="110px"></iframe>
<p><em>You can listen to more articles from The Conversation, narrated by Noa, <a href="https://theconversation.com/uk/topics/audio-narrated-99682">here</a>.</em></p>
<p>Journalists brought in by Ukrainian troops who have retaken various towns around the capital have been <a href="https://www.ft.com/content/855fb1f0-a3ce-40a7-89fd-23a43aae3614">shown bodies of civilians</a> with their hands tied, apparently executed, as well as evidence that women were raped before being murdered. If confirmed, this would be evidence that the Russian forces committed war crimes. It will be up to the investigators to determine this.</p>
<p>The work of <a href="https://en.wikipedia.org/wiki/Forensic_anthropology#Forensic_archaeology">forensic archaeologists</a> and <a href="https://en.wikipedia.org/wiki/Forensic_anthropology">forensic anthropologists</a> tends to focus on finding and identifying people’s bodies so that the remains can be returned to their families and given a proper burial. But there is also the question in many cases of how the person died. This is key for providing transitional justice after a conflict like the war raging in Ukraine, where there is now a search for evidence to prove criminal activity on the part of the occupying troops. </p>
<h2>Search for the missing</h2>
<p>The search for missing individuals in hidden graves usually starts with <a href="https://doi.org/10.1111/1556-4029.14168">researching an area</a> prior to any physical work. This can include taking witness testimony, examining old maps and photographs, using remote sensing and aerial photography as well as examining available digital data, such as geolocated tagged and dated images from mobile phones. Investigators will also look for any changes to the landscape that might be hiding a grave. Once a suspect area has been identified – and this can be in fields, caves, wells, forests, buildings or in water – the initial challenge is to find the grave itself. </p>
<p>The <a href="https://www.bbc.co.uk/news/world-europe-60981228">recent discovery of mass graves</a> in Ukraine was made using remote sensing satellite images. This technology has been <a href="https://doi.org/10.1080/00085030.2006.10757132">routinely used</a> to find victims since mass graves were found during the Iraq wars in the 1990s. Specialist victim recovery search dogs, <a href="https://doi.org/10.1016/j.forsciint.2018.06.020">drones</a> and <a href="https://doi.org/10.1016/j.forsciint.2018.03.034">geophysics surveys</a> (including experienced metal detector teams) can all assist with grave detection. Non-invasive geophysics <a href="http://dx.doi.org/10.1016/j.forsciint.2013.12.036">can detect hidden victims</a> behind walls and even under concrete. But this is difficult, and the resulting intrusive work to try to identify human remains is painstaking and slow. </p>
<p>Searching for victims in water is also possible with modern <a href="https://en.wikipedia.org/wiki/Sonar">sonar</a> and <a href="https://dx.doi.org/10.3390/rs13132542">water penetrating radar</a> surveys. But this is both time intensive and time critical, as remains will fall apart after long periods of immersion, depending on site-specific factors such as water depth and currents and water oxygen levels. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-science-of-finding-buried-bodies-77803">The science of finding buried bodies</a>
</strong>
</em>
</p>
<hr>
<h2>Recovering victims</h2>
<p>Once anomalous areas in the ground have been identified, these are excavated by hand or by mechanical digger, supervised by forensic archaeologists and other professionals. Excavation techniques may vary but aim to capture as much data as possible on the position and location of bodies within the grave, as well as any items associated with the body which may allow for correct identification. The goal will also be to find any other evidence that may assist with an investigation into criminal activity, such as when the grave was originally dug or how it was subsequently excavated after being discovered. </p>
<p>Careful <a href="https://doi.org/10.1016/j.forsciint.2019.109943">digital data capture methods</a>, such as drones or ground scanners, should be used to record forensic evidence as it is recovered so it could be later presented in court. This can include contemporaneous objects such as discarded cigarettes, bullet casings and the bullets themselves, which may help to identify when a victim was killed and potentially yield ballistic evidence that could help identify the perpetrators. All of this should follow <a href="https://doi.org/10.1016/j.forsciint.2021.110716">standard forensic protocols</a>, including chain of custody. </p>
<h2>Identifying the deceased</h2>
<p>In the mortuary, forensic anthropologists, dentists and pathologists will examine remains from a burial site to work out how many individuals are present and assist in identifying them.</p>
<p>In 20th-century conflicts, forensic anthropologists are often needed to examine <a href="https://doi.org/10.1016/j.forsciint.2021.110706">human skeletal remains</a> and assess age at death, biological sex, and any other identifying features. Sometimes they are still required for this work. But these days positive identification tends instead to mainly rely on DNA, fingerprints, dental work or any unique characteristics of the individual during life compared with the information obtained from the body after death.</p>
<p>It is important to <a href="https://www.icrc.org/en/publication/0880-management-dead-bodies-after-disasters-field-manual-first-responders">understand this process</a> and manage family expectations regarding the limitations of forensic methods, length of time for analysis and to be aware of any ethical, cultural and religious practices with the human remains.</p>
<p>Forensics teams will also look for evidence of trauma to the body relating to combat, blast injuries, as well as execution (for example, gunshot wounds to the back of the head). This can be complicated by alterations to the body made after death – such as attempts to burn the corpse – but can usually <a href="https://doi.org/10.1016/j.forsciint.2017.03.014">still be detected</a>. </p>
<p>It is important that these <a href="https://www.cambridge.org/es/academic/subjects/archaeology/archaeological-science/scientific-investigation-mass-graves-towards-protocols-and-standard-operating-procedures?format=HB&isbn=9780521865876">processes are undertaken by professionals</a> in order to maximise the evidence recovered and avoid as much as possible any mis-identifications. </p>
<p>In all cases the <a href="https://www.icrc.org/en/what-we-do/forensic-action">dignity of the deceased’s remains</a> is of primary importance, as well as letting the victims’ families know what happened. It’s also very important for the relatives of the deceased to be able to give their family member a proper burial. These events should not happen but sadly they do and it is our job to document them.</p><img src="https://counter.theconversation.com/content/180765/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jamie Pringle receives funding from the HLF, the Nuffield Foundation, Royal Society, NERC, EPSRC and EU Horizon2020. He is affiliated with the Geological Society of London. Jamie works for Keele University.</span></em></p><p class="fine-print"><em><span>Nicholas Marquez-Grant does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The grisly work of forensic investigators at the scene of a possible war crime.Jamie Pringle, Reader in Forensic Geoscience, Keele UniversityNicholas Marquez-Grant, Senior Lecturer in Forensic Anthropology, Cranfield UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1719592021-11-18T02:19:57Z2021-11-18T02:19:57ZHow do police forensic scientists investigate a case? A clandestine gravesite recovery expert explains<figure><img src="https://images.theconversation.com/files/432536/original/file-20211117-17-12mhnhc.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5729%2C3739&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Brendan Chapman</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Recent high-profile missing persons cases, including that of William Tyrrell – who went missing in Kendall, New South Wales, at the age of three in 2014 – have focused public attention on the forensic practices involved in crime scene investigations. </p>
<p>As a forensic scientist who has worked at thousands of homicide, sexual assault and serious crime scenes, I can tell you this process is not as straightforward as depicted on popular true crime shows.</p>
<p>I <a href="https://scholar.google.com.au/citations?user=RxkDXXAAAAAJ&hl=en">research</a> and teach <a href="https://www.murdoch.edu.au/thisisfreethinking/home">forensic science at Murdoch University</a> and specialise in <a href="https://www.murdoch.edu.au/news/articles/cold-case-review-at-murdoch">cold-case</a> techniques and clandestine gravesite recovery. Here’s what typically happens behind the lines of police tape when forensic teams are at work.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/this-is-going-to-affect-how-we-determine-time-since-death-how-studying-body-donors-in-the-bush-is-changing-forensic-science-117662">'This is going to affect how we determine time since death': how studying body donors in the bush is changing forensic science</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/432534/original/file-20211117-17-a8pr7v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/432534/original/file-20211117-17-a8pr7v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/432534/original/file-20211117-17-a8pr7v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432534/original/file-20211117-17-a8pr7v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432534/original/file-20211117-17-a8pr7v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432534/original/file-20211117-17-a8pr7v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432534/original/file-20211117-17-a8pr7v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432534/original/file-20211117-17-a8pr7v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The author teaches students clandestine grave site evidence collection techniques to Murdoch University students.</span>
<span class="attribution"><span class="source">Brendan Chapman</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>The crucial first moments</h2>
<p>In the first moments after a major crime, what has happened is often a mystery. </p>
<p>Like a scene from a painting, it’s as if time stood still; many regular household items sit as they did before the violent event took place. Investigators take great care not to disturb the initial scene, lest valuable evidence be lost.</p>
<p>The first task is to record everything as it appears in incredible detail – by video, photo and in written notes. Even items that may first appear innocuous can later take on new significance.</p>
<p>This stage is vital; years later, this may be the only way cold-case teams can virtually revisit the scene to identify new clues. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/432531/original/file-20211117-28-9dneev.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/432531/original/file-20211117-28-9dneev.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/432531/original/file-20211117-28-9dneev.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432531/original/file-20211117-28-9dneev.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432531/original/file-20211117-28-9dneev.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432531/original/file-20211117-28-9dneev.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432531/original/file-20211117-28-9dneev.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432531/original/file-20211117-28-9dneev.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The first task, before anything in the scene is disturbed, is to record everything as it appears.</span>
<span class="attribution"><span class="source">Brendan Chapman</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Evidence testing and collection</h2>
<p>As the forensic investigation unfolds, information and evidence are gathered and given to investigators at the crime scene. This helps provide context to guide the search for evidence.</p>
<p>The crime scene team works meticulously to identify and “field-test” items (meaning tests are done in situ) before securing them in bags. </p>
<p>In some cases, that’s by using chemicals and testing kits to identify body fluids or other traces associated with the crime. </p>
<p>We also use some very high-tech torches that can emit a specific type to light to help us see otherwise invisible clues. This works a bit like the lighting in nightclubs that might expose lint on your black outfit.</p>
<p>At this stage, the best crime scene examiners invoke the scientific method, proposing <a href="https://wires.onlinelibrary.wiley.com/doi/10.1002/widm.1354">hypotheses</a> as to what has happened, and then searching for evidence that may refute their suggestion. </p>
<p>Theories are presented and then ruled out in place of new theories as new evidence emerges. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/432295/original/file-20211116-27-102xibz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/432295/original/file-20211116-27-102xibz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/432295/original/file-20211116-27-102xibz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432295/original/file-20211116-27-102xibz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432295/original/file-20211116-27-102xibz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432295/original/file-20211116-27-102xibz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432295/original/file-20211116-27-102xibz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432295/original/file-20211116-27-102xibz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The crime scene team works meticulously to identify and field test items of evidence before securing them in bags.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Testing for traces of blood, semen and other body fluids</h2>
<p>On the scene, forensic investigators have a suite of tools to help identify body fluids such as semen and blood.</p>
<p>The <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2523691/?page=1">Kastle–Meyer test</a>, deployed to test for the possible presence of blood, has been used since the early 20th century.</p>
<p>A chemical called phenolophthalin is dropped onto the suspected sample, followed quickly by a drop of hydrogen peroxide. These chemicals can detect the blood ingredient haemoglobin. If it rapidly turns pink, there’s a good chance there’s blood in the sample.</p>
<p>A different method called the acid phosphatase test, which can detect an enzyme secreted from the prostate gland, is used to identify the presence of semen. A prepared chemical is dropped onto a sample of the suspected stain; a colour change from clear to dark purple suggests the likely presence of semen.</p>
<p>You may also have heard of investigators using <a href="https://www.abc.net.au/news/2021-11-17/william-tyrrell-investigation-technology-explained/100626684">luminol</a>, which can detect old blood stains or traces a person has tried to scrub away. The investigator sprays luminol and other chemicals on a darkened area; a blue glow suggests traces of blood may be present.</p>
<p>For all these tests, and everything we do as forensic investigators, meticulous records are kept about both observations and ideas. These notes will eventually become part of the huge case file that goes to court. </p>
<h2>Different types of forensic experts work together</h2>
<p>There are many different types of specialist crime scene investigators, such as:</p>
<ul>
<li><p><strong>fingerprint specialists</strong>, who use chemicals and powders to visualise fingerprints invisible to the naked eye and determine if they’re good enough to compare with prints on a database</p></li>
<li><p><strong>bloodstain pattern analysis experts</strong> who, like Dexter from the eponymous crime show, observe the shape of blood droplets or marks in an effort to reconstruct a bloodshed scenario</p></li>
<li><p><strong>physical evidence comparison experts</strong>, who record evidence such as shoe impressions or tool marks to compare with objects at the scene (for example, was <em>this</em> screwdriver used to create <em>that</em> mark on a window frame?)</p></li>
<li><p><strong>ballistics and firearms experts</strong>, who identify and analyse evidence such as gunshot residues and fired bullets. They can also reconstruct shooting events to determine trajectories and distances</p></li>
<li><p><strong>clandestine grave recovery experts</strong> (like me!), whose knowledge of the natural processes after death can help <a href="https://link.springer.com/article/10.1007/s11896-021-09457-8?wt_mc=Internal.Event.1.SEM.ArticleAuthorOnlineFirst&utm_source=ArticleAuthorOnlineFirst&utm_medium=email&utm_content=AA_en_06082018&ArticleAuthorOnlineFirst_20210521">locate and exhume grave sites</a> using painstakingly careful archaeological approaches. </p></li>
</ul>
<p>Other specialised forensic practitioners include pathologists, <a href="https://theconversation.com/trust-me-im-an-expert-forensic-entomology-or-what-bugs-can-tell-police-about-when-someone-died-124416">insect experts</a>, anthropologists, biologists and chemists. </p>
<p>Forensic investigations are most successful with a <a href="https://www.emerald.com/insight/content/doi/10.1108/JCP-09-2019-0038/full/html">multidisciplinary</a> team, which allows for many different opinions and ideas. </p>
<p>Specialists must work together to ensure one person’s evidence-collection method doesn’t ruin another specialist’s chance to use their own techniques.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/trust-me-im-an-expert-forensic-entomology-or-what-bugs-can-tell-police-about-when-someone-died-124416">Trust Me, I'm An Expert: forensic entomology, or what bugs can tell police about when someone died</a>
</strong>
</em>
</p>
<hr>
<h2>Clandestine gravesites</h2>
<p>Outdoor scenes present extra challenges, as evidence can be damaged or destroyed by weather, wildlife and the landscape itself. Clandestine gravesites, however, can help preserve clues underground.</p>
<p>It’s not easy to find a hidden burial site; even a freshly dug gravesite, if done well, can be difficult to identify in an expansive bush scene. </p>
<p>Investigators will be looking for areas where the ground looks disturbed or spots where vegetation has grown unusually lushly (caused by the decomposition of a body underneath).</p>
<p>Investigators may also deploy cadaver dogs to search for human remains, or <a href="https://www.abc.net.au/news/2021-11-17/william-tyrrell-investigation-technology-explained/100626684">ground-penetrating radar</a>, which uses radio waves to identify changes in the soil underground.</p>
<p>Once a grave is identified, you can’t just roughly dig it up; the grave fill must be gradually removed using small brushes and shovels, like those used on archaeological dig sites.</p>
<p>All removed soil is sifted and searched for tiny pieces of evidence; even a tiny fibre or hair could connect the grave to a suspect. </p>
<p>Even the sidewalls of the grave can offer clues about the type or shape of the shovel used to dig it. </p>
<p>Layer by layer, we work down until we reveal the deceased person at the bottom of the grave. Utmost care is taken here, as repatriation of the remains to loved ones is a pivotal part of the process of gaining closure.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/432533/original/file-20211117-23-qhvavi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/432533/original/file-20211117-23-qhvavi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/432533/original/file-20211117-23-qhvavi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/432533/original/file-20211117-23-qhvavi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/432533/original/file-20211117-23-qhvavi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/432533/original/file-20211117-23-qhvavi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/432533/original/file-20211117-23-qhvavi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/432533/original/file-20211117-23-qhvavi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">It’s not easy to find a hidden burial site; even a freshly dug gravesite, if done well, can be very difficult to identify in an expansive bush scene.</span>
<span class="attribution"><span class="source">Brendan Chapman</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Time is of the essence</h2>
<p>All evidence has a life span. The sooner forensic scientists can identify and analyse a piece of evidence, the better the chances are of it producing a result. </p>
<p>This can be one of the greatest challenges in a cold case, where a crime scene has been changed by the elements over many years.</p><img src="https://counter.theconversation.com/content/171959/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Brendan Chapman does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>As a forensic scientist who has worked at thousands of homicide, sexual assault and serious crime scenes, I can tell you the process is not as straightforward as depicted on popular true crime shows.Brendan Chapman, Senior Lecturer in Forensic Science, Murdoch UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1616862021-08-18T18:26:48Z2021-08-18T18:26:48ZWe trained AI to recognise footprints, but it won’t replace forensic experts yet<figure><img src="https://images.theconversation.com/files/405926/original/file-20210611-23-1xdb1cf.jpg?ixlib=rb-1.1.0&rect=251%2C233%2C3544%2C1982&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/black-wet-footprints-over-gray-pedestrian-638543815">Shutterstock/Evannovostro</a></span></figcaption></figure><p>We rely on experts all the time. If you need financial advice, you ask an expert. If you are sick, you visit a doctor, and as a juror you may listen to an expert witness. In the future, however, artificial intelligence (AI) might replace many of these people. </p>
<p>In forensic science, the expert witness plays a vital role. Lawyers seek them out for their analysis and opinion on specialist evidence. But experts are human, with all their failings, and the role of expert witnesses has frequently been <a href="https://doi.org/10.1073/pnas.1712161115">linked to</a> miscarriages of justice.</p>
<p>We’ve been investigating the potential for AI to study evidence in forensic science. In two recent papers, we found AI was better at assessing footprints than general forensic scientists, but not better than specific footprint experts.</p>
<h2>What’s in a footprint?</h2>
<p>As you walk around your home barefoot you leave footprints, as <a href="https://doi.org/10.1111/1556-4029.14718">indentations in your carpet</a> or as residue from your feet. Bloody footprints are common at violent crime scenes. They allow investigators to reconstruct events and perhaps profile an unknown suspect.</p>
<p>Shoe prints are one of the <a href="https://doi.org/10.1111/1556-4029.14662">most common</a> types of evidence, especially <a href="https://doi.org/10.1016/j.scijus.2021.04.003">at domestic burglaries</a>. These traces are recovered from windowsills, doors, toilet seats and floors and may be visible to or hidden from the naked eye. In the UK, recovered marks are analysed by police forces and used to search <a href="https://www.policeprofessional.com/news/the-national-footwear-reference-collection-nfrc/">a database</a> of footwear patterns.</p>
<p>The size of barefoot prints can tell you about a suspect’s height, weight, and even gender. In a<a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0255630"> recent study</a>, we asked an expert podiatrist to determine the gender of a bunch of footprints and they got it right just over 50% of the time. We then created a neural network, a form of AI, and asked it to do the same thing. It got it right around 90% of the time. What’s more, much to our surprise, it could also assign an age to the track-maker at least to the nearest decade.</p>
<figure class="align-center ">
<img alt="A series of footprints with a heat map over them." src="https://images.theconversation.com/files/405889/original/file-20210611-17-1wr8c6w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/405889/original/file-20210611-17-1wr8c6w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=368&fit=crop&dpr=1 600w, https://images.theconversation.com/files/405889/original/file-20210611-17-1wr8c6w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=368&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/405889/original/file-20210611-17-1wr8c6w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=368&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/405889/original/file-20210611-17-1wr8c6w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=463&fit=crop&dpr=1 754w, https://images.theconversation.com/files/405889/original/file-20210611-17-1wr8c6w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=463&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/405889/original/file-20210611-17-1wr8c6w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=463&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The footprints analysed by the Bluestar AI, with a heat map over them suggesting areas of ambiguity.</span>
<span class="attribution"><span class="source">Matthew Bennett</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>When it comes to shoe prints, footwear experts can identify the make and model of a shoe simply by experience – it’s second nature to these experts and mistakes are rare. Anecdotally, we’ve been told there are fewer than 30 footwear experts in the UK today. However, there are thousands of forensic and police personnel in the UK who are casual users of the the footwear database. For these casual users, analysing footwear can be challenging and their work often needs to be verified by an expert. For that reason, we thought AI may be able to help.</p>
<p>We tasked a second neural network, developed as part of an ongoing partnership with UK-based <a href="https://doi.org/10.1016/j.asoc.2021.107496">Bluestar Software</a>, with identifying the make and model of footwear impressions. This AI takes a black and white footwear impression and automatically recognises the shape of component treads. Are the component treads square, triangular or circular? Is there a logo or writing on the shoe impression? Each of these shapes corresponds to a code in a simple classification. It is these codes that are used to search the database. In fact the AI gives a series of suggested codes for the user to verify and identifies areas of ambiguity that need checking.</p>
<p>In one of our experiments, an occasional user was given 100 randomly selected shoe prints to analyse. Across the trial, which we ran several times, the casual user got it right between 22% and 83% of the time. In comparison the AI was between 60% and 91% successful. Footwear experts, however, are right nearly 100% of the time. </p>
<p>One reason why our second neural network was not perfect and didn’t outperform real experts is that shoes vary with wear, making the task more complex. Buy a new pair of shoes and the tread is sharp and clear but after a month or two it becomes less clear. But while the AI couldn’t replace the expert trained to spot these things it did outperform occasional users, suggesting it could help free up time for the expert to focus on more difficult cases. </p>
<h2>Will AI replace experts?</h2>
<p>Systems like this increase the accuracy of footwear evidence and we will probably see it used more often than it is currently – especially in intelligence-led policing that aims to link crimes and reduce the cost of domestic burglaries. In the UK alone they cost on average £5,930 per incident in 2018, which amounts to <a href="https://www.gov.uk/government/publications/the-economic-and-social-costs-of-crime">a total economic cost</a> of £4.1 billion. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/it-takes-a-lot-of-energy-for-machines-to-learn-heres-why-ai-is-so-power-hungry-151825">It takes a lot of energy for machines to learn – here's why AI is so power-hungry</a>
</strong>
</em>
</p>
<hr>
<p>AI will never replace the skilled and experienced judgement of a well-trained footwear examiner. But it might help by reducing the burden on those experts and allow them to focus on the difficult cases by helping the casual users to identify the make and model of a footprint more reliably on their own. At the same time, the experts who use this AI will replace the ones who don’t.</p><img src="https://counter.theconversation.com/content/161686/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Matthew Robert Bennett receives funding from the UK Knowledge Transfer Partnership (KTP). </span></em></p><p class="fine-print"><em><span>Marcin Budka receives funding from Innovate UK via the Knowledge Transfer Partnership (KTP) programme.</span></em></p>Artificial intelligence could help police catch criminals – but we need human experts for the big cases.Matthew Robert Bennett, Professor of Environmental and Geographical Sciences, Bournemouth UniversityMarcin Budka, Professor of Data Science, Bournemouth UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1299272020-01-29T11:35:45Z2020-01-29T11:35:45ZAI could revolutionise DNA evidence – but right now we can’t trust the machines<figure><img src="https://images.theconversation.com/files/312242/original/file-20200128-81362-vo3fpm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/helix-diagram-dna-against-pulse-track-609777710">vectorfusionart/Shutterstock</a></span></figcaption></figure><p>DNA evidence often isn’t as watertight as many people think. Sensitive techniques developed over the past 20 years mean that police can now detect minute traces of DNA at a crime scene or on a piece of evidence. But traces from a perpetrator are often mixed with those from many other people that have been transferred to the sample site, for example via a handshake. And this problem has led to people being <a href="https://www.theguardian.com/science/2017/oct/02/dna-in-the-dock-how-flawed-techniques-send-innocent-people-to-prison">wrongly convicted</a>.</p>
<p>Scientists have developed algorithms to separate this DNA soup and to measure the relative amounts of each person’s DNA in a sample. These “<a href="https://scholarship.law.berkeley.edu/cgi/viewcontent.cgi?article=1143&context=bjcl">probabilsitic genotyping</a>” methods have enabled forensic investigators to indicate how likely it is that an individual’s DNA was included in a mixed sample found at the crime scene.</p>
<p>And now, more sophisticated artificial intelligence (AI) techniques are being developed in an attempt to <a href="https://www.dundee.ac.uk/leverhulme/projects/details/machine-learning-and-feature-extract-of-dna-profiles.php">extract DNA profiles</a> and try to work out whether a DNA sample came directly from someone who was at the crime scene, or whether it had just been innocently transferred.</p>
<p>But if this technology is successful, it could introduce a new problem, because it’s currently impossible to understand exactly how this AI reaches its conclusions. And how can we trust technology to provide vital evidence if we can’t interrogate how it produced that evidence in the first place? It has the potential to open the way to even more miscarriages of justice and so this lack of transparency may be a barrier to the technology’s use in forensic investigations.</p>
<p>Similar challenges emerged when DNA analysis software was first developed a decade ago. Evidence derived from DNA mixture software very quickly ran <a href="https://www.theguardian.com/uk-news/2016/jun/07/killer-dna-evidence-genetic-profiling-criminal-investigation">into challenges</a> from defence teams (including <a href="https://www.sandiegouniontribune.com/sdut-oj-simpson-trial-dna-evidence-fx-2016apr16-story.html">that of OJ Simpson</a>), who were concerned that the prosecution should demonstrate that the software was correctly validated. </p>
<p>How accurate were the results, and what was the known error rate? How exactly did the software work and could it accommodate defence hypotheses? Were the results really so dependable that a jury could safely convict?</p>
<p>It is a fundamental tenet of the law that evidence must be <a href="https://dl.acm.org/doi/10.1145/3306618.3314279">open to scrutiny</a>. The jury cannot rely on bald assertions (claims made without evidence), no matter who makes them and what expertise they have. But the owners of the software argued it was their protected intellectual property and how it worked shouldn’t be made public.</p>
<p>A <a href="https://www.nytimes.com/2017/09/04/nyregion/dna-analysis-evidence-new-york-disputed-techniques.html">battle ensued</a> that involved the use of <a href="http://www.abajournal.com/magazine/article/code_of_science_defense_lawyers_want_to_peek_behind_the_curtain_of_probabil/P1">novel court procedures</a> to allow defence teams to privately examine how the software worked. Finally, the courts were persuaded that full access to the source code was needed, not least to test hypotheses other than those put forward by the prosecution. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/312245/original/file-20200128-81395-alz9no.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/312245/original/file-20200128-81395-alz9no.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/312245/original/file-20200128-81395-alz9no.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/312245/original/file-20200128-81395-alz9no.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/312245/original/file-20200128-81395-alz9no.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/312245/original/file-20200128-81395-alz9no.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/312245/original/file-20200128-81395-alz9no.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">AI can predict whether someone was actually at the site of a DNA sample.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/senior-female-scientist-works-high-tech-1073659400">Gorodenkoff/Shutterstock</a></span>
</figcaption>
</figure>
<p>But the software hasn’t completely solved the issues of DNA mixtures and small, degraded samples. We still don’t know definitively if the DNA in a sample came directly from a person or was transferred there. This is complicated by the fact that different people shed DNA at different rates – a phenomenon known as their “shedder status”.</p>
<p>For example, a sample taken from a murder weapon could contain more DNA from someone who hasn’t touched it than from the person who actually committed the murder. People have <a href="https://www.themarshallproject.org/2018/04/19/framed-for-murder-by-his-own-dna">been charged with serious offences</a> because of this.</p>
<p>Add the fact that DNA is transferred at different rates across different surfaces and in different environmental conditions and it may become almost impossible to know exactly where DNA in a sample came from. This problem of “<a href="https://www.themarshallproject.org/2018/04/19/framed-for-murder-by-his-own-dna">transfer and persistence</a>” threatens to seriously undermine forensic DNA.</p>
<p>As a result, <a href="https://www.sciencedirect.com/science/article/abs/pii/S1872497319300444">experiments are underway</a> to find ways of more accurately quantifying DNA transfer in different circumstances. And AI has the potential to analyse the data from these experiments and use it to indicate the origin of DNA in a sample.</p>
<p>But AI-based software has an even greater transparency problem than probabilistic genotyping software did, and one that’s currently fundamental to the way it works. The exact way the software works isn’t just a commercial secret – it’s unclear even to the software developers.</p>
<h2>Transparency issues</h2>
<p>AI uses mathematical algorithms to complete tasks such as matching a facial expression to a particular set of emotions. But, crucially, it is <a href="https://www.cmswire.com/information-management/ai-vs-algorithms-whats-the-difference/">able to learn</a> through a process of trial and error and gradually manipulates its underlying algorithms in order to become more efficient.</p>
<p>It’s this process of manipulation and change that isn’t always <a href="https://www.idgconnect.com/idgconnect/opinion/1026262/transparent-vs-opaque-ai">transparent.</a> The software makes its changes incredibly rapidly according to its own indecipherable logic. It can derive fantastically efficient results but we can’t say how it did so. It acts like a black box that takes inputs and gives outputs, but whose inner workings are invisible. Programmers can go through a clearer development process but it is slower and less efficient.</p>
<p>This transparency issue affects many broader applications of AI. For example, it makes it very difficult to correct AI systems whose decisions display a <a href="https://theconversation.com/ai-could-be-a-force-for-good-but-were-currently-heading-for-a-darker-future-124941">racial or gender bias</a>, such those used to sift through employee resumes, or to target police resources. </p>
<p>And the advent of AI-driven DNA analysis will add a further dimension to the problems already encountered. Defence lawyers could rightly challenge the use of this technology, even if its use is limited to intelligence gathering rather than providing prosecution evidence. Unless transparency problems are addressed at an early stage, the obstacles to AI use in the forensic field could prove insurmountable.</p>
<p>How might we go about tackling these challenges? One option may be to opt for the less efficient, constrained forms of AI. But if the purpose of AI is to do the tasks we are less capable of or less willing to do ourselves, then reducing efficiency may be a poor solution. Whichever form of AI we opt to use, within an adversarial system of criminal justice there must be the potential for review, to reverse-engineer all automated decisions, and for third parties to provide unambiguous validation.</p>
<p>Ultimately, this is not merely a technical issue, but an urgent ethical problem that goes to the heart of our criminal justice systems. At stake is the right to a fair, open and transparent trial. This is a fundamental requirement that must be addressed before the headlong rush of technological advancement carries us past the point of no return.</p><img src="https://counter.theconversation.com/content/129927/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Karen Richmond does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>No one knows exactly how AI-based DNA analysis software works, so it can’t be scrutinised in court.Karen Richmond, Postdoctoral research fellow, University of Strathclyde Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1230202019-09-10T20:07:06Z2019-09-10T20:07:06ZForensic science isn’t ‘reliable’ or ‘unreliable’ – it depends on the questions you’re trying to answer<figure><img src="https://images.theconversation.com/files/291710/original/file-20190910-109919-df9a8o.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3866%2C2562&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Footprints aren't always as clear as this - but they nevertheless have their uses.</span> <span class="attribution"><span class="source">Eddies Images/Shutterstock.com</span></span></figcaption></figure><p>After recent criticism in the US and the UK, forensic science is now coming under attack in Australia. Several recent reports have detailed concerns that innocent people have been <a href="https://www.smh.com.au/national/top-judge-worried-forensic-evidence-putting-innocent-people-behind-bars-20190823-p52k3l.html">jailed because of flawed forensic techniques</a>.</p>
<p>Among the various cases presented, it is surprising that the most prominent recent miscarriage of justice in Victoria did not rate a mention: the wrongful conviction of <a href="https://www.smh.com.au/national/wrongfully-accused-20140324-35cga.html">Farah Jama</a>, who was found guilty of rape in 2008 before the verdict was overturned in 2009. </p>
<p>This omission is not entirely unexpected. The forensic evidence in the case against Jama was DNA. Despite this fact, the recent media comments have re-emphasised the view that DNA is the gold standard when it comes to forensic techniques. Justice Chris Maxwell, president of the Victorian Court of Appeal, <a href="https://www.smh.com.au/national/top-judge-worried-forensic-evidence-putting-innocent-people-behind-bars-20190823-p52k3l.html">said</a>: </p>
<blockquote>
<p>…with the exception of DNA, no other area of forensic science has been shown to be able reliably to connect a particular sample with a particular crime scene or perpetrator.</p>
</blockquote>
<p>How can the same technique simultaneously be the forensic gold standard and contribute to such a dramatic miscarriage of justice? Is forensic science so unreliable that none of it should be admissible in our courts? Of course not, otherwise the criminal justice system would be left relying on much less reliable evidence, such as witness statements and confessions.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/get-real-forensic-scientists-the-csi-effect-is-waning-13260">Get real, forensic scientists: the CSI effect is waning</a>
</strong>
</em>
</p>
<hr>
<h2>Evidence in context</h2>
<p>It makes no sense to assess the reliability of any forensic technique in the abstract. A forensic method is only “reliable” as far as it helps answer the particular questions asked in the context of a particular case. Asking the wrong questions will undoubtedly deliver the wrong answers, even if the best and most fully validated forensic method is applied.</p>
<p>Conversely, some forensic methods are perceived by some commentators to have less intrinsic value or even questionable reliability. But these methods might yield the answer to a crucially relevant question. </p>
<p>A typical example would be an incomplete shoe mark of poor quality left at a crime scene. It might not be possible to assign this mark to a specific shoe, but it might be enough to exclude a particular shoe or to identify the direction in which the perpetrator walked.</p>
<p>Forensic science is much more than merely applying methods or conducting tests – success also depends on the ability to identify and answer a relevant question. </p>
<p>A forensic science system is not like a clinical laboratory, processing samples and producing results for prescribed tests. Rather, good forensic science requires collaboration between investigators, scientists and other stakeholders. The focus should be resolving judicial questions using a scientific approach. </p>
<p>What matters most is the detection, recognition and understanding of the traces left by individuals during an alleged crime. This a much more complex issue than simply deciding whether or not a particular forensic method is deemed “reliable”.</p>
<h2>Complex process</h2>
<p>Forensic science is much less cut-and-dried than television dramas might suggest. When a DNA swab or a shoe mark lands on a forensic scientist’s lab bench, it has already gone through many steps, each with their own uncertainties. </p>
<p>These uncertainties are unavoidable, because forensic traces typically represent the aftermath of a chaotic event. The only option is to manage these uncertainties through a better understanding of how these traces are generated, persist, degrade, interact with each other, and how the information they hold can be interpreted.</p>
<p>The debate about the reliability of forensic science is not new. It illustrates a more fundamental issue: the lack of understanding of forensic science among the general public (who are potential jurors), and even among highly reputable law practitioners and non-forensic scientists.</p>
<h2>Legacy of reform</h2>
<p>The high-profile <a href="https://www.ncjrs.gov/pdffiles1/nij/grants/228091.pdf">2009 US National Academy of Sciences report</a> and the <a href="https://obamawhitehouse.archives.gov/sites/default/files/microsites/ostp/PCAST/pcast_forensic_science_report_final.pdf">2016 Obama Administration report</a>, both of which criticised some uses of forensic evidence, prompted an international reaction and several reviews of forensic practices. </p>
<p>They justified more empirical research to support some forensic conclusions. These improvements have been occurring in Australia for some years under the leadership of the National Institute of Forensic Science and through several academic research programs. And the recent UK House of Lords enquiry into the state of forensic science in England and Wales identified the Australian forensic science model as a leading example.</p>
<p>However, these reports excluded crime scene management from the scientific domain. They provided limited guidance about the challenging topic of interpretation of forensic evidence. This is disturbing because these are the two areas that require most attention if we are serious about improving forensic science outcomes.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/this-is-going-to-affect-how-we-determine-time-since-death-how-studying-body-donors-in-the-bush-is-changing-forensic-science-117662">'This is going to affect how we determine time since death': how studying body donors in the bush is changing forensic science</a>
</strong>
</em>
</p>
<hr>
<p>As the recent media coverage has shown, evidence interpretation remains a sore point between the legal and scientific communities. Where is the boundary of the responsibility of science versus the law? The fact that the legal community poorly understands forensic evidence is undoubtedly a shared responsibility. Shifting the blame onto forensic science will only exacerbate the problem.</p>
<p>If we think this is all too hard with traditional physical evidence, how does the criminal justice system expect to cope with our rapidly evolving digital society? Digital evidence is typically harder to assess than physical evidence in terms of volume, variety, rapidity, and privacy issues.</p>
<p>Better education, research and collaboration will form a large part of the answer. They will induce a better understanding of forensic science and its fundamental principles, so it can serve justice with confidence.</p><img src="https://counter.theconversation.com/content/123020/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Claude Roux receives funding from the Australian Research Council including Linkage grants with the Australian Federal Police, the Victoria Police, the NSW Health Pathology and Rofin Australia Pty Ltd, and from the US National Institute of Justice. He is the President of the International Association of Forensic Sciences (2017-2020), current Vice-President of the Australian Academy of Forensic Sciences, the immediate Past-President of the Australian & New Zealand Forensic Science Society (ANZFSS) and a Fellow of the Royal Society of New South Wales. He also serves on the Scientific Advisory Board of the International Criminal Court.</span></em></p>The debate about the reliability of forensic evidence reflects a lack of understanding of how forensic science is best used in the justice system, rather than a problem with forensic science itself.Claude Roux, Distinguished Professor of Forensic Science, University of Technology SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1209742019-08-29T20:03:50Z2019-08-29T20:03:50ZIf you’ve been sexually assaulted, here’s what doctors and nurses do next<figure><img src="https://images.theconversation.com/files/288846/original/file-20190821-170927-1rpwko0.jpg?ixlib=rb-1.1.0&rect=1%2C7%2C997%2C658&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Doctors and nurses will collect vital evidence and arrange care with understanding and compassion at a traumatic time.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/1023504136?src=XJXnzCOOOn47I8imkvXFlg-1-1&size=medium_jpg">from www.shutterstock.com</a></span></figcaption></figure><p>Sexual assault is a traumatic event that affects people in different ways, both mentally and physically. So doctors and nurses know care immediately after an assault needs to be understanding, compassionate and sensitive.</p>
<p>This is particularly so during forensic examinations where the main purpose is to collect evidence as quickly as possible after, but within 72 hours, of the assault. This evidence may be vital to secure a conviction and may be lost or contaminated if there is a delay. </p>
<p>So, what happens during the forensic medical examination? And if you’ve been sexually assaulted, what can you expect?</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/rape-sexual-assault-and-sexual-harassment-whats-the-difference-93411">Rape, sexual assault and sexual harassment: what’s the difference?</a>
</strong>
</em>
</p>
<hr>
<p>People who have been sexually assaulted, be they adult or children, can expect slightly different procedures depending on their state or territory. The general principles, however, remain the same. </p>
<p>To support a conviction, evidence is required to connect the victim to the offender at a particular location. In most cases, specially trained doctors or nurses collect this evidence when you go to a hospital or clinic.</p>
<p>But first, they will ensure you don’t have an injury or condition needing urgent medical care as this needs to be treated beforehand. The forensic practitioner will then explain the process and seek your consent to proceed. </p>
<p>They will ask you for an account of the assault to know which evidence to collect. They will examine you, document injuries and collect the evidence.</p>
<h2>What evidence will they collect and how?</h2>
<p>The doctor or nurse uses what’s known as a “rape kit” to collect evidence. This kit contains the necessary material, including swabs, forceps, collection bags, labels and seals.</p>
<p>Evidence may consist of your clothing; swabs of your skin; swabs taken from the anus and genital region including the vagina; fingernail scrapings; and samples from any biological or other external material found.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/you-catch-criminals-with-dna-what-kids-know-and-dont-know-about-genetics-13964">'You catch criminals with DNA': What kids know (and don't know) about genetics</a>
</strong>
</em>
</p>
<hr>
<p>The doctor or nurse may collect blood and urine samples if drugs or toxins are involved, for instance if there’s a chance you could have been drugged or poisoned. They will also take a swab from inside your mouth as a reference sample of your DNA.</p>
<p>DNA contamination is possible, in one instance it has resulted in an innocent man being <a href="https://www.wiley.com/en-us/Current+Practice+in+Forensic+Medicine%2C+Volume+2-p-9781118455982">sent to jail</a>. Several measures are in place to minimise the chance of this happening. An unopened rape kit is certified DNA-free. And doctors and nurses will examine you in a “<a href="https://www.wiley.com/en-us/Current+Practice+in+Forensic+Medicine%2C+Volume+2-p-9781118455982">clean room</a>” if available. These dedicated forensic rooms are carefully cleaned after each examination to reduce DNA contamination.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/from-the-crime-scene-to-the-courtroom-the-journey-of-a-dna-sample-82250">From the crime scene to the courtroom: the journey of a DNA sample</a>
</strong>
</em>
</p>
<hr>
<p>Once the doctor or nurse collects the evidence from you, they seal it to ensure it is not tampered with and if it is, this can be detected. They then hand over the evidence to a police officer, who delivers it to the forensic laboratory. </p>
<p>The process of transfer of evidence from the forensic practitioner to the laboratory is known as chain of custody. Should this documented chain be broken, the integrity of the evidence comes into question (could someone have tampered with it?) and it may not be admissible in court.</p>
<h2>Doctors and nurses support you in other ways</h2>
<p>Beyond collecting evidence, the forensic practitioner has other duties. They will ensure you receive any follow-up medical and mental health care.</p>
<p>That might include treating your injuries, giving you medicine (prophylaxis) to prevent sexually transmitted infections and giving you the morning-after-pill to prevent pregnancy.</p>
<p>The doctor or nurse will also ensure you have transport to get to a safe refuge after leaving the hospital or clinic.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/288848/original/file-20190821-170941-5aglz5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/288848/original/file-20190821-170941-5aglz5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/288848/original/file-20190821-170941-5aglz5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/288848/original/file-20190821-170941-5aglz5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/288848/original/file-20190821-170941-5aglz5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/288848/original/file-20190821-170941-5aglz5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/288848/original/file-20190821-170941-5aglz5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/288848/original/file-20190821-170941-5aglz5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Doctors and nurses will co-ordinate your medical care and make sure you have a safe place to go after leaving hospital.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/nurse-holding-phone-while-searching-folder-107831300?src=2G6--8yVEs-8Ko01z9Chew-1-72">www.shutterstock.com</a></span>
</figcaption>
</figure>
<p>Their final task is to write a medico-legal report detailing what they found when they examined you and what evidence was collected. This report may be required in court and may contain an expert opinion if provided by a forensic doctor.</p>
<p>Depending upon the circumstances and protocols in place, the police may interview you briefly before the forensic examination and then again, but in more detail, afterwards. If you go to hospital late at night, this second interview may be delayed until the next day.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/its-hard-to-think-about-but-frail-older-women-in-nursing-homes-get-sexually-abused-too-107013">It's hard to think about, but frail older women in nursing homes get sexually abused too</a>
</strong>
</em>
</p>
<hr>
<h2>Who will examine you?</h2>
<p>Doctors or nurses who perform sexual assault examinations need specialised knowledge of forensic and legal medicine. So, like other specialised areas of medicine, there are a limited number of facilities available in regional and remote areas to perform these examinations.</p>
<p>However, even if you live in an area without specialised forensic facilities, you can still be examined and evidence collected. In this case, forensic doctors can guide a local doctor or a nurse through the examination by providing advice over the phone. This can occur even without a rape kit by using pathology collection equipment present in all hospitals and clinics.</p>
<p>In these cases, the medico-legal reports don’t contain opinions about the case. They just contain the facts.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/getting-doctors-to-the-bush-depends-on-more-than-just-uni-places-41972">Getting doctors to the bush depends on more than just uni places</a>
</strong>
</em>
</p>
<hr>
<p>No adult or child who has been sexually assaulted should need to travel great distances or wait excessive times to receive appropriate forensic care.</p>
<p>And if this <a href="https://www.abc.net.au/news/2019-06-28/rape-investigations-hampered-by-lack-of-qualified-forensic-staff/11258476">does happen in regional and remote areas</a>, this is usually down to not having enough facilities rather than doctors and nurses refusing to perform the examinations.</p>
<p>Competent evidence collection may be undertaken in any hospital or clinic. This is vital. Without this evidence, convictions may fail and perpetrators may be set free. Although often tedious and at times uncomfortable and tiring, these examinations are essential to ensure justice.</p>
<hr>
<p><em>If this article has raised issues for you or someone you know, contact <a href="https://www.1800respect.org.au">https://www.1800respect.org.au</a> or call 1800 737 732, the National Sexual Assault, Domestic and Family Violence Counselling Service.</em></p><img src="https://counter.theconversation.com/content/120974/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Gall is President of the International Association of Clinical Forensic Medicine (formerly World Police Medical Officers), past Vice-President of the Australasian Association of Forensic Physicians, member of the Chemical Pathology Advisory Committee of the Royal College of Pathologists of Australasia, a member the Australian Medical Association and member of the Liberal Party of Australia. He is the Principal of Era Health, Melbourne, and a Staff Specialist at the Royal Children's Hospital and Monash Children's Hospital, Melbourne.</span></em></p>What happens during a forensic medical examination? And if you’ve been sexually assaulted, what can you expect?John Gall, Clinical Associate Professor and Forensic Physician, Department of Paediatrics, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1176622019-07-01T19:43:07Z2019-07-01T19:43:07Z‘This is going to affect how we determine time since death’: how studying body donors in the bush is changing forensic science<p>On the outskirts of Sydney, in a secret bushland location, lies what’s officially known as the <a href="https://www.uts.edu.au/about/faculty-science/after-facility/about-us">Australian Facility for Taphonomic Experimental Research</a> (AFTER). In books and movies, it’d be called a body farm. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/280632/original/file-20190621-149831-3k0kka.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/280632/original/file-20190621-149831-3k0kka.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/280632/original/file-20190621-149831-3k0kka.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/280632/original/file-20190621-149831-3k0kka.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/280632/original/file-20190621-149831-3k0kka.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/280632/original/file-20190621-149831-3k0kka.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/280632/original/file-20190621-149831-3k0kka.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/280632/original/file-20190621-149831-3k0kka.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Maiken Ueland at the AFTER facility run by UTS.</span>
<span class="attribution"><span class="source">Supplied by UTS</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Taphonomy is the study of how an organism breaks down after death. Research underway at the University of Technology Sydney’s AFTER facility is yielding some surprising new findings about how bodies decompose in the Australian bush.</p>
<p>And here’s an astonishing detail: until AFTER opened in Sydney in 2016, there was no facility like it in the southern hemisphere. Most of the world’s taphonomic research came from the US, meaning we were missing vital clues relating to how Australian weather, bugs and climate conditions affect the way a human body decomposes in the bush.</p>
<p>Today on our podcast, <a href="https://theconversation.com/au/podcasts/trust-me-podcast">Trust Me, I’m An Expert</a>, we take you on a journey to AFTER. The facility’s interim director, Maiken Ueland, and PhD student Samara Garrett-Rickman share with us:</p>
<ul>
<li>some of the unexpected findings emerging from AFTER on determining time since death;</li>
<li>why AFTER researchers prefer not to use the term “body farm”;</li>
<li>how the stages of decomposition work </li>
<li>a process of “mummification” that research suggests may be unique to Australian bushland conditions;</li>
<li>what the TV shows get wrong about forensic science; </li>
<li>why it’s harder to bury a body than most people think; </li>
<li>what investigators look for to spot a clandestine grave;</li>
</ul>
<p>And if you’re interested in finding out more about how to donate your body for such research, you can start <a href="https://www.uts.edu.au/about/faculty-science/after-facility/body-donation">here</a>. </p>
<h2>New to podcasts?</h2>
<p>Podcasts are often best enjoyed using a podcast app. All iPhones come with the Apple Podcasts app already installed, or you may want to listen and subscribe on another app such as Pocket Casts (click <a href="https://pca.st/VTv7">here</a> to listen to Trust Me, I’m An Expert on Pocket Casts).</p>
<p>You can also hear us on Stitcher, Spotify or any of the apps below. Just pick a service from one of those listed below and click on the icon to find Trust Me, I’m An Expert.</p>
<p><a href="https://itunes.apple.com/au/podcast/trust-me-im-an-expert/id1290047736?mt=2&ign-mpt=uo%3D8"><img src="https://images.theconversation.com/files/233721/original/file-20180827-75984-1gfuvlr.png" alt="Listen on Apple Podcasts" width="268" height="68"></a> <a href="https://www.google.com/podcasts?feed=aHR0cHM6Ly90aGVjb252ZXJzYXRpb24uY29tL2F1L3BvZGNhc3RzL3RydXN0LW1lLXBvZGNhc3QucnNz"><img src="https://images.theconversation.com/files/233720/original/file-20180827-75978-3mdxcf.png" alt="" width="268" height="68"></a></p>
<p><a href="https://www.stitcher.com/podcast/the-conversation/trust-me-im-an-expert"><img src="https://images.theconversation.com/files/233716/original/file-20180827-75981-pdp50i.png" alt="Stitcher" width="300" height="88"></a> <a href="https://tunein.com/podcasts/News--Politics-Podcasts/Trust-Me-Im-An-Expert-p1035757/"><img src="https://images.theconversation.com/files/233723/original/file-20180827-75984-f0y2gb.png" alt="Listen on TuneIn" width="318" height="125"></a></p>
<p><a href="https://radiopublic.com/trust-me-im-an-expert-Wa3E5A"><img class="alignnone size-medium wp-image-152" src="https://images.theconversation.com/files/233717/original/file-20180827-75990-86y5tg.png?ixlib=rb-1.1.0&q=45&auto=format&w=268&fit=clip" alt="Listen on RadioPublic" width="268" height="87"></a> <a href="https://open.spotify.com/show/7myc7drbLJVaRitAMXLB7V"><img src="https://images.theconversation.com/files/237984/original/file-20180925-149976-1ks72uy.png?ixlib=rb-1.1.0&q=45&auto=format&w=268&fit=clip" width="268" height="82"></a> </p>
<hr>
<h2>Additional audio</h2>
<p>Kindergarten by Unkle Ho, from <a href="https://www.elefanttraks.com/">Elefant Traks.</a></p>
<p>Backyard by <a href="http://freemusicarchive.org/music/David_Szesztay/20170730112627760/Backyard_1620">David Szesztay</a> from Free Music Archive</p>
<h2>Images</h2>
<p>UTS/Anna Zhu</p><img src="https://counter.theconversation.com/content/117662/count.gif" alt="The Conversation" width="1" height="1" />
On the outskirts of Sydney, in a secret bushland location, lies what's officially known as the Australian Facility for Taphonomic Experimental Research. In books or movies, it'd be called a body farm.Sunanda Creagh, Senior EditorLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/974082018-11-06T16:46:50Z2018-11-06T16:46:50Z‘It is the job of the living to save the dead from drowning’<figure><img src="https://images.theconversation.com/files/243241/original/file-20181031-76384-1bi69v6.jpg?ixlib=rb-1.1.0&rect=0%2C24%2C1500%2C963&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The remains of an Ixil man emerge from the ground, one of the countless victims of the civil war in Guatemala. </span> <span class="attribution"><span class="source">Tristan Brand/FAFG Fundacion de Antropologia Forense de Guatemala</span>, <span class="license">Author provided</span></span></figcaption></figure><p>I arrive in Buenos Aires in December. My fieldwork in Guatemala has ended and that in Argentina has not yet begun. I am in between things. I’ve been working with a team of forensic anthropologists exhuming mass graves and piecing together bones, labouring to identify victims of Guatemala’s recent history of political violence. After months of intimate proximity to death and terror, it is strange to arrive in the sunny cheer of Buenos Aires.</p>
<p>It’s high summer in Argentina, vacation time. I’m disoriented by the (to me) upside-down seasons of the Southern Hemisphere. I’m startled to find myself wandering the Palermo Soho neighbourhood, where tourists sip café cortados at sidewalk cafes. In leafy Parque Centenario, people practice yoga, folding themselves into the downward-dog position. I am a world away from Guatemala City with its barred windows and cautious streets. It is hard to believe that a few weeks ago I was standing in the mud of an excavation site in the remote province of Quiché, excavating bones.</p>
<p>In Guatemala, I was always with other people. We dug together and ate meals together. We shared rooms, clothes, mosquito spray, water bottles and colds. In Argentina, I am alone. My newly rented studio apartment is as bare and white as a clinic: white tiled floor, white walls, white curtains. In the bright summer light, I feel like I’m living inside an eggshell.</p>
<p>When do I realise I am not well? When I hear people laughing as they pass on the street and rush to close the curtains so they won’t glimpse me? When I skip dinner and sit hungry on the edge of my bed rather than go outside? Odd things enter my mind: a woodcut print I once saw of children in a garden. Above them, puffy summer clouds. Below them, roots of trees and plants sinking into the earth – and tangled among the roots, skeletons.</p>
<p>I constantly think of three men, how their bones were crisscrossed in the dirt. Why this exhumation and not one of the others? I don’t know, but this particular mass grave in the hills of El Quiché is always present, like a radio playing in the background. The strata of copper-tinged soil. The women from the community, arms folded, waiting at the edge of the excavation. The sound of the river and the pick axes.</p>
<h2>200,000 dead and 45,000 disappeared</h2>
<p>There are hundreds of mass graves in Guatemala. During the <a href="https://www.theguardian.com/global-development/2018/jun/14/disappeared-guatemala-family-search-son-marco-antonio-molina-theissen">armed conflict from 1960 to 1996</a>, the Guatemalan military, supported by the US government, targeted Maya farming communities for their supposed sympathy with leftist guerrilla groups. Entire villages were massacred. The United Nations estimates that <a href="https://journals.openedition.org/amerika/3880">83% of the victims were indigenous Maya-speaking Guatemalans</a>. The scale of the violence is staggering: in a country with a population of 8 million people, 200,000 were killed and 45,000 disappeared. El Quiché was at the epicentre of the bloodshed: locally, the conflict is known simply as <a href="http://berkeleyjournal.org/2017/03/la-violencia-after-war-the-long-legacy-of-conflict-in-guatemala/"><em>La Violencia</em></a> – the violence.</p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/242455/original/file-20181026-7056-bq9ruo.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/242455/original/file-20181026-7056-bq9ruo.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=660&fit=crop&dpr=1 600w, https://images.theconversation.com/files/242455/original/file-20181026-7056-bq9ruo.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=660&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/242455/original/file-20181026-7056-bq9ruo.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=660&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/242455/original/file-20181026-7056-bq9ruo.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=829&fit=crop&dpr=1 754w, https://images.theconversation.com/files/242455/original/file-20181026-7056-bq9ruo.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=829&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/242455/original/file-20181026-7056-bq9ruo.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=829&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The province of El Quiche, Guatemala.</span>
<span class="attribution"><a class="source" href="https://fr.wikipedia.org/wiki/D%C3%A9partement_du_Quich%C3%A9">Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Standing in the exhumation site, <a href="http://eprints.kingston.ac.uk/35562/">we dig to find the buried bones</a>. We uncover three male skeletons. Tidy bullet holes, entry and exit, mark two of the crania; the third skull is completely shattered. As we clean away the dirt, Maxi tells us to look for machete marks, which appear as lines etched across the bone. In other mass graves, on other skeletons, we have found the tell-tale hatch marks on skulls, scapula, fibula (a blow to sever the Achilles tendon, so people can’t run away). This is the kind of forensic detail we are being trained to spot and document. It can be used as evidence to prove torture and murder, to build a case for genocide in a trial. If there ever is a trial.</p>
<p>Toothbrushes, brooms, dustpans, pink and green plastic buckets. Maxi stopped at the Walmart outside of Guatemala City to buy supplies. The tools for exhuming mass graves are ordinary. We work for hours cleaning dirt off the three bodies, careful not to displace their position in the grave. It is not the bones I find most disturbing. It is not the skulls with their expression of grinning or screaming. It is not even the cord still tied around the intricate bones of one man’s wrists. It is the boots. All the local men wear these exact boots. When I look up from my work, I see these very boots gathered around the grave, worn by the men watching us, the men hoping to find their missing father, brother, son. After work, I scrape the mud from my shoes, using a stick, just as I use a stick to clean the mud from the soles of the dead men’s boots.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/242449/original/file-20181026-7053-rkuw7k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/242449/original/file-20181026-7053-rkuw7k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/242449/original/file-20181026-7053-rkuw7k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/242449/original/file-20181026-7053-rkuw7k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/242449/original/file-20181026-7053-rkuw7k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/242449/original/file-20181026-7053-rkuw7k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/242449/original/file-20181026-7053-rkuw7k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Workers unearth human remains in the province of Quiché, Guatemala. Thousands of bodies have been discovered. Of the more than 200,000 people murdered or missing, 83% were indigenous-language speakers.</span>
<span class="attribution"><span class="source">Tristan Brand/FAFG Fundacion de Antropologia Forense de Guatemala</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The three dead men are dressed in typical work clothes. As I brush the dirt off a plaid shirt, I can feel the sharp ribs beneath the fabric. I notice the even stitching of the homemade shirt. The fabric is intact and retains its colours. Some of the thread along the sleeve has rotted away (cotton degrades faster than nylon), leaving the fabric in pieces. I imagine the wives and mothers who cut and stitched the cloth.</p>
<p>Maxi tells me that when the bodies of women are found wearing <em>traje</em> (traditional dress), women from the community ask for photographs of their <em>huipil</em>, their handwoven blouses, and sometimes climb into the grave to inspect the stitching. The design of a <em>huipil</em> is unique and can give a clue to the identity of a skeleton. If a woman finds the body of her mother, she may have the same <em>huipil</em> made for herself and her daughters.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/242450/original/file-20181026-7056-1qhuv2v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/242450/original/file-20181026-7056-1qhuv2v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/242450/original/file-20181026-7056-1qhuv2v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/242450/original/file-20181026-7056-1qhuv2v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/242450/original/file-20181026-7056-1qhuv2v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/242450/original/file-20181026-7056-1qhuv2v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/242450/original/file-20181026-7056-1qhuv2v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">An Ixil woman participates in the search to find the remains of her brother, Quiche province.</span>
<span class="attribution"><span class="source">Tristan Brand/FAFG Fundacion de Antropologia Forense de Guatemala</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Recognition by <em>huipil</em> is not scientific identification. Bodies are also sometimes found with jewellery, visible tattoos and even legible identification documents. Such evidence is noted and forms part of a forensic profile. It can help establish identity, dependent on the findings of a forensic exam, and ideally, a DNA match. But identity documents can end up with someone other than their original owner. People have similar tattoos. Jewellery gets stolen. Clothes get switched.</p>
<p>Families and community members may find clothing more convincing than a forensic identification or even a DNA match. It can be hard to imagine a skeleton – or often just a fragment of bone – as a son or mother. A watch, a tattoo, a driver’s license – any of these may be more hospitable to the imaginative work entailed in accepting human remains as a missing loved one. (For more on the complications of associating bone fragments with missing people, see Renshaw, 2016 and Wagner, 2008.) Families and forensic teams sometimes measure evidence by different standards and find certainty in different forms of proof.</p>
<h2>Locating the dead</h2>
<p>In Guatemala, these different ways of knowing <a href="https://www.interventionjournal.com/content/pau-p%C3%A9rez-sales-susana-navarro-garc%C3%ADa-2007resistencias-contra-el-olvido-trabajo-psicosocial">converge on dreams</a>. In the Maya cosmovision, the dead play an active role in the lives of the living. Dreams are one of the principal channels of communication, a means by which ancestors offer counsel and give warning. From a young age, children are encouraged to remember and tell their dreams. (For more on dreams in Maya society, see Pérez-Sales and Navarro Garcia 2007; Tedlock, 1981; and Molesky-Poz, 2009. For children’s dream training, see Tedlock, 1981.) In the context of exhumations, community members report dreams in which the dead indicate where their body is located so that it can be found and given a proper burial. Without funeral rites, the dead are not at peace and cannot fulfil their communal role. (Pérez-Sales and Navarro-Garcia, 2007. For a well-documented discussion of communication between living and dead in the context of exhumation in East Timor, see Kinsella and Blau, 2013.) Exhumation helps restore the correct relationship between the living and the dead.</p>
<p>Community members seek to <a href="https://www.stabilityjournal.org/articles/10.5334/sta.au/">locate bodies through dreams</a>, but the forensic team chooses where to excavate based on archaeological evidence. They look for subtle changes in the topography that may indicate a sunken area. They dig exploratory trenches looking for signs that the dirt is <em>revuelto</em>, the layers mixed together, which is an indication that it has been previous disturbed.</p>
<h2>Dead bodies can’t drown</h2>
<p>I want to know how these competing methods of locating bodies affect the relationship between teams and communities. I ask Zulma, who is the director of an organisation that provides practical and psychological support to communities during the process of exhumation. Zulma is a social worker who grew up in Quiché, wears the <em>traje</em> of her village, and speaks Ixil and Spanish. She acts as an interpreter, not only linguistically, but socially, between the local communities, the forensic team, and other NGOs and government actors. She tells me that for Maya communities, DNA is important and dreams are too. When I ask if she feels like the forensic teams takes the dreams reported to them seriously, she pauses and says, “We have to be patient with the scientists. They have a different way of seeing the world.” She adds, “more than anything, they are interested in the colour of soil, but we are interested in dreams.”</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/242452/original/file-20181026-7071-1f1xms1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/242452/original/file-20181026-7071-1f1xms1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=288&fit=crop&dpr=1 600w, https://images.theconversation.com/files/242452/original/file-20181026-7071-1f1xms1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=288&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/242452/original/file-20181026-7071-1f1xms1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=288&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/242452/original/file-20181026-7071-1f1xms1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=362&fit=crop&dpr=1 754w, https://images.theconversation.com/files/242452/original/file-20181026-7071-1f1xms1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=362&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/242452/original/file-20181026-7071-1f1xms1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=362&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Exhumation helps to restore normal relations between the living and the dead.</span>
<span class="attribution"><span class="source">Alicia Andre/Penninghen</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>I ask Alvaro, a Spanish-speaking forensic archaeologist, what role dreams play in the team’s work. He says that just a week before, a woman approached him to relate a dream indicating that her father was buried under a big pine tree at the current site. I ask if the team will search there. He says, “We have to respect the way they see the world.” Then he sighs and says, “but there are a lot of pine trees!”</p>
<p>The site being excavated sits at the edge of a forest. We are digging by a large pine tree, whose thick roots make the shovelling hard going. It is already late in the day when we find the first bone. The air is heavy with approaching rain. As Alvaro scrapes away the earth from the femur, local men prepare a tarp to protect the site from the impending storm. In a flash of a machete blade they chop branches from trees, cutting supports and stakes cleverly notched to fit together. Maxi once said that one of the tragedies of La Violencia was that it disgraced the machete. It brought shame to a noble instrument that harvests maize and builds houses. So much death dealt by machetes, so many massacres. A tool of life made a weapon of death. The men at the site wield machetes with grace and magic, making tents over the open pits in minutes.</p>
<p>The rain begins to pour down, but the team keeps working under the tarp, fuelled by a buzz of excitement that we have found a grave. Within an hour, the distinct forms of three bodies are visible. They are skeletonized, meaning that all the flesh has decomposed and that only bone is left. There seem to be more bodies farther beneath. Alvaro guesses seven in total.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/242454/original/file-20181026-7056-u7xev3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/242454/original/file-20181026-7056-u7xev3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/242454/original/file-20181026-7056-u7xev3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/242454/original/file-20181026-7056-u7xev3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/242454/original/file-20181026-7056-u7xev3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/242454/original/file-20181026-7056-u7xev3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/242454/original/file-20181026-7056-u7xev3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A member of the FAFG team takes a picture of some of the remains found, including a piece of a broken skull.</span>
<span class="attribution"><span class="source">Tristan Brand/FAFG Fundacion de Antropologia Forense de Guatemala</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>On the ride back to town, as the truck inches through the downpour, Maxi and Alvaro tell a story. During an exhumation in another community, a hard rain began to fall. The excavated pit with its half-exposed bodies quickly filled with water. Community members jumped in to save the people buried there from drowning. The punchline of this story is, of course, that dead bodies can’t drown.</p>
<p>A story about the dead drowning marks a boundary between the team and the families. It separates a biomedical conception of the corpse from an understanding of the dead as still in some sense vital. It divides science from the sacred. Such a boundary might seem unassailable, but the longer my fieldwork goes on, the less sure I am about the stability of such divisions. I begin to think that the boundary between scientific and non-scientific world-views is more like a porous membrane than a cement wall.</p>
<h2>Not just dreams</h2>
<p>It is not just dreams that unsettle the boundary between science and something else. It is also the potential liveliness of bones. In a lab, I see a forensic anthropologist stroke the forehead of a skull with tender touch and say, “poor guy,” as she records the trauma she reads in his bones. I notice a team member cringe when hammering a segment of femur to prepare a DNA sample. When I ask her about it, she says, “I hate doing it. It feels wrong. After everything they’ve been through.” A member of the Argentine forensic team remarks that she abhors the part of the lab protocol that requires her to place skulls in plastic bags. “It’s stupid but I feel like they’re suffocating.”</p>
<p>These are not strictly scientific reactions. The worry of suffocation is not so different than the worry of drowning. Tender touch, a visceral reluctance to break a bone or place a skull in a plastic bag imply a certain continued vitality to bones and a vulnerable personhood that persists in the dead. As Katharine Young has remarked about prohibitions against dark humour during autopsies, you can only offend a subject, not an object. So, too, it is subjects not objects who can be injured and cared for.</p>
<p>Perhaps “care” is the boundary that matters. It is not a boundary that divides scientific and non-scientific or families and forensic teams, it is one that encloses them in the same field. The field of care includes cleaning bones and examining the stitching of a <em>huipil</em>. It encompasses both dreams and DNA. As archaeologist Rosemary Joyce and human rights scholar Adam Rosenblatt have pointed out, forensic anthropologists are among the few groups of people socially sanctioned to care for dead bodies. Families and forensic teams share the duty of caring for the dead. It is the job of the living to save the dead from drowning.</p>
<hr>
<p><em>The article on which this translation is based was published in collaboration with the <a href="https://blogterrain.hypotheses.org/">blog of the journal Terrain</a>. The illustrations and photos were kindly provided by the students of the <a href="https://www.penninghen.fr/">Penninghen School</a> and by the photographer <a href="https://tristanbrand.photoshelter.com/gallery-image/Guatemala-Forensics/G00008wpP3TKzdIQ/I0000l1S.emeNVQg">Tristan Brand</a> with the FAFG Fundacion de Antropologia Forense de Guatemala.</em></p><img src="https://counter.theconversation.com/content/97408/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alexa Hagerty has worked with the FAFG Fundacion de Antropologia Forense de Guatemala.</span></em></p><p class="fine-print"><em><span>Laure Assaf is a member of the editorial team of the review Terrain.</span></em></p>The Ixil people of Guatemala dream of the places where their dead, massacred during the country’s armed conflict might be located.Alexa Hagerty, Anthropologist, Stanford UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/983992018-06-25T10:36:57Z2018-06-25T10:36:57ZWe’ve discovered a way to recover DNA from fingerprints without destroying them<figure><img src="https://images.theconversation.com/files/224406/original/file-20180622-26555-1tqkaxq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/criminology-expert-through-magnifying-glass-looking-523427320?src=m2JKjJUib3YVWTQf99N1Ag-2-59">Shutterstock</a></span></figcaption></figure><p>Fingerprints hold a <a href="https://theconversation.com/the-hidden-data-in-your-fingerprints-95491">lot more information</a> than you might realise. They don’t just provide a pattern with which to identify people. They can also contain DNA. And as neither DNA nor fingerprints are infallible ways of working out who was at a location, combining both pieces of evidence could be vital for investigators.</p>
<p>The problem is that forensic scientists usually have to choose between one or the other, as recovering DNA can mean destroying the fingerprint and vice versa. However, my colleagues and I have discovered <a href="https://www.sciencedirect.com/science/article/pii/S0379073816303334?via%3Dihub">a new method</a> that could collect both types of evidence at once.</p>
<p>Fingerprints, referred to as “fingermarks” in forensics, are formed when residue from the ridged skin of the fingers or palms is transferred onto a surface, leaving behind an impression. Fingermarks are often made of sweat and colourless contaminating materials such as soap, moisturiser and grease. These fingermarks are described as “latent” as they are generally invisible to the naked eye, which means that locating them at a crime scene can be challenging.</p>
<p>Sweat can contain DNA so it’s possible <a href="https://www.forensicmag.com/article/2012/06/touch-dna-analysis-using-literature-help-answer-some-common-questions">to retrieve it</a> from latent fingermarks, although the success of the technique very much depends on the quantity and quality of the DNA. As crime scenes are not sterile environments, it’s also possible for latent fingermarks to be contaminated with DNA from the same person or from different people. </p>
<p>But to find latent fingermarks, investigators often need to brush a surface with powder that <a href="http://www.crime-scene-investigator.net/fingerprintingtechniqscontamination.pdf">may contaminate</a> or <a href="https://www.sciencedirect.com/science/article/pii/S1875176811002617?via%3Dihub">damage the DNA</a>. Another way to detect fingermarks is to use light sources, such as ultraviolet light torches, but the process isn’t always reliable and it can also degrade DNA. There is a process for recovering DNA, which involves rubbing a swab over the fingermark or lifting it using special tape, something which can in turn make the fingermark unusable.</p>
<p>Of course, not all fingermarks left at crime scenes are valuable as evidence. Some are simply smudges or are deposited onto surfaces that affect their quality. But without being able to see them and determine their potential as evidence, scientists must often choose whether to recover the DNA or the fingermarks. <a href="https://www.sciencedirect.com/science/article/pii/S0379073816303334?via%3Dihub">Our new process</a> involves applying a soft, low-adhesive gel material to the surface for a couple of seconds to recover any DNA-containing material while leaving any fingermarks intact.</p>
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<img alt="" src="https://images.theconversation.com/files/224411/original/file-20180622-26549-10slr9f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/224411/original/file-20180622-26549-10slr9f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/224411/original/file-20180622-26549-10slr9f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/224411/original/file-20180622-26549-10slr9f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/224411/original/file-20180622-26549-10slr9f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/224411/original/file-20180622-26549-10slr9f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/224411/original/file-20180622-26549-10slr9f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Double source of evidence.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/fingerptint-isolated-on-black-704200345?src=jhPwcKtou8JOPUB1E8oPBg-3-15">Shutterstock</a></span>
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<p>So far we have successfully recovered DNA and fingermarks on several surfaces that are likely to be encountered at crime scenes, including textured plastics and paper, with no statistically significant differences in the quality of the marks. In some instances, the process actually improved the quality of the fingermarks where it removed excessive residue.</p>
<p>As a result of this technique, investigators could have an extra source of evidence. This would be useful if any collected fingermarks turn out not to be enough to identify someone or establish that someone had been in a certain location or touched a certain object.</p>
<h2>Improving the technique</h2>
<p>So far, we’ve found it difficult to use the gel to recover DNA and latent fingermarks from very smooth surfaces such as glass. This is partly because these marks are generally more exposed and fragile. We are working to overcome this problem by considering alternative novel, less adhesive DNA-recovery techniques. We’re also trying to find ways to establish the quality of fingermarks before they are recovered that don’t involve contact, using infrared and thermal imaging devices.</p>
<p>We are also looking at the effects of DNA recovery on blood fingermarks, and from fingermarks deposited onto surfaces that are contaminated with alternative biological fluids, such as semen and saliva. These fluids often contain higher quantities of DNA than sweat-based latent fingermarks. This means it might be possible to use a less adhesive DNA-recovery method on them, which could reduce the impact on any fingermarks.</p>
<p>Ultimately, we want to produce a simple and timely method that can be used without extensive training or expense, but that could significantly increase the scope for identifying criminals.</p><img src="https://counter.theconversation.com/content/98399/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sarah Fieldhouse does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Lifting fingermarks from a crime scene often destroys the DNA they can contain.Sarah Fieldhouse, Senior Lecturer in Forensic Science, Staffordshire UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/855342017-10-23T19:07:51Z2017-10-23T19:07:51ZFingerprinting to solve crimes: not as robust as you think<figure><img src="https://images.theconversation.com/files/191295/original/file-20171022-13934-bnw0xm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">There's a margin of error in relying on fingerprinting to catch criminals. </span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/police-takes-fingerprints-criminal-law-concept-524699446?src=3-DyRQZYszIkTc0lL081Ww-1-58">from www.shutterstock.com </a></span></figcaption></figure><p>Police have used fingerprint evidence to catch and convict criminals for <a href="http://www.hup.harvard.edu/catalog.php?isbn=9780674010024">more than 100 years</a>. It’s a commonly used technique in Australia: more than <a href="http://www.police.vic.gov.au/content.asp?Document_ID=771">10,000 fingerprint matches</a> were made in Victoria alone last year.</p>
<p>But in a <a href="https://www.aaas.org/report/latent-fingerprint-examination">recent report</a>, the American Association for the Advancement of Science has questioned the scientific validity of fingerprint analysis.</p>
<p>The report is a reminder that although fingerprinting is an essential tool for investigating crime, <a href="http://scholarlycommons.law.northwestern.edu/cgi/viewcontent.cgi?article=7201&context=jclc">it’s not infallible</a>. We need to minimise the inappropriate application of the “science” of fingerprinting, and reduce repeats of <a href="http://digitalcommons.law.ggu.edu/ggulrev/vol37/iss1/4/">miscarriages of justice</a> linked to fingerprint analysis that have already occurred.</p>
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Read more:
<a href="https://theconversation.com/forensic-evidence-largely-not-supported-by-sound-science-now-what-67413">Forensic evidence largely not supported by sound science – now what?</a>
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<p>Most notoriously, <a href="https://oig.justice.gov/special/s0601/exec.pdf">Brandon Mayfield</a>, an American lawyer, was wrongly linked by four fingerprint experts to the 2004 Madrid train bombing. He was arrested and detained for two weeks, before investigators realised that an Algerian man, Ouhnane Daoud, was the real source of the print. </p>
<h2>How does fingerprint examination work?</h2>
<p>Everybody’s fingers, palms and soles have “friction ridges” on them. These ridges occur in patterns (such as <a href="https://forsci.wikispaces.com/Fingerprinting">arches and loops</a>) that contain specific features (for example, ridge endings and dots). </p>
<p>Fingerprint examiners <a href="https://www.crcpress.com/Fingerprints-and-Other-Ridge-Skin-Impressions-Second-Edition/Champod-Lennard-Margot-Stoilovic/p/book/9781498728935">use these patterns</a> and features to compare an unknown (or “latent”) print with a known print, to determine if they may have come from the same person.</p>
<p>In Australia, police use the <a href="https://www.acic.gov.au/our-services/biometric-matching/national-automated-fingerprint-identification-system">National Automated Fingerprint Identification System</a> – a database with more than <a href="https://www.australianpolice.com.au/dactyloscopy/automated-fingerprint-identification-system-afis/">2.6 million</a> sets of fingerprints - to narrow down the field of fingerprints to compare. But the final decision about whether there is a “match” is made by a person.</p>
<p>A 2010 report, published by the US National Institute of Justice, concluded that <a href="http://www.crime-scene-investigator.net/fingerprintsourcebkchp6.pdf">automated systems</a> were significantly less accurate than well-trained examiners at making comparisons between latent and known prints.</p>
<h2>Problems with the underlying science</h2>
<p>Until the mid-2000s, little scientific research had been done on most forensic disciplines, including fingerprinting. This lack of research became widely publicised in 2009, when the US National Research Council published a <a href="https://www.ncjrs.gov/pdffiles1/nij/grants/228091.pdf">landmark report</a> on the forensic sciences. </p>
<p>It found that the only forensic method that had been rigorously validated was nuclear DNA analysis. All other forensic sciences – including fingerprinting – lacked a proper scientific foundation. </p>
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Read more:
<a href="https://theconversation.com/from-the-crime-scene-to-the-courtroom-the-journey-of-a-dna-sample-82250">From the crime scene to the courtroom: the journey of a DNA sample</a>
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<p>When examining this issue again in 2016, the President’s Council of Advisors on Science and Technology (<a href="https://obamawhitehouse.archives.gov/sites/default/files/microsites/ostp/PCAST/pcast_forensic_science_report_final.pdf">PCAST</a>) in the US found that only two properly designed studies of latent fingerprint analysis had been conducted. These both found the rate of false matches (known as “false positives”) to be very high: <a href="https://www.ncjrs.gov/pdffiles1/nij/grants/248534.pdf">1 in 18</a> and <a href="https://www.ncbi.nlm.nih.gov/pubmed/21518906">1 in 30</a>. </p>
<p>One of the main reasons for these high error rates is that fingerprint analysis involves human judgement, and relies on a methodology (known as “ACE-V”) that is <a href="http://scholarlycommons.law.northwestern.edu/cgi/viewcontent.cgi?article=7201&context=jclc">not sufficient</a> to ensure the accuracy and reliability of an examiner’s conclusions. This means there is no guarantee that two different examiners who follow its steps will reach the same result. </p>
<h2>Recent improvements</h2>
<p>Since the National Research Council report was released, scientists have <a href="https://obamawhitehouse.archives.gov/sites/default/files/microsites/ostp/PCAST/pcast_forensic_science_report_final.pdf">worked hard to prove</a> that fingerprint examination is scientific. </p>
<p><a href="https://www.aaas.org/report/latent-fingerprint-examination">Research</a> has now convincingly established that the ridge patterns on fingers vary greatly among individuals, and that there is little variation in a person’s fingerprints over time. This provides a scientific basis for using fingerprints to distinguish individuals, even identical twins. </p>
<p>But there is still <a href="https://www.aaas.org/report/latent-fingerprint-examination">no scientific basis</a> for concluding that a print must have been left by a specific person, or even for estimating the number of people who might be the source of a print. </p>
<p>The most that can be said is that two prints have many corresponding features, with no differences that would indicate they were made by different fingers. It may also be possible for an examiner to say that the set of features found in the prints is unusual.</p>
<h2>Cognitive bias</h2>
<p>Because fingerprint analysis depends heavily on human judgement, an examiner’s conclusions may be improperly influenced by non-scientific factors, such as <a href="https://www.nist.gov/publications/latent-print-examination-and-human-factors-improving-practice-through-systems-approach">irrelevant contextual information</a>. </p>
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Read more:
<a href="https://theconversation.com/explainer-how-law-enforcement-decodes-your-photos-78828">Explainer: how law enforcement decodes your photos</a>
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<p>This phenomenon, which is known as “<a href="https://www.journals.elsevier.com/journal-of-applied-research-in-memory-and-cognition/target-articles/forensic-confirmation-bias-problems-perspectives">cognitive bias</a>”, has been demonstrated in various studies. </p>
<p>In <a href="http://www.sciencedirect.com/science/article/pii/S0379073805005876">one study</a>, five fingerprint experts were told they were comparing Brandon Mayfield’s fingerprint with the fingerprint found in Madrid. They were asked whether they would also have (wrongly) found a match. </p>
<p>In reality, the experts were given fingerprints from a different case they had personally found to match years earlier, in the normal course of their casework. Four of the five experts changed their opinion. This was seen to be due to their expectation that the fingerprints did not match.</p>
<p><a href="https://www.ncbi.nlm.nih.gov/pubmed/22212067">Another study</a> found that fingerprint examiners can be improperly influenced by the use of automated fingerprint identification systems, which provide ordered lists of the most likely matches. </p>
<p>The study found that examiners are more likely to wrongly identify one of the prints near the top of the list as a match, and to fail to make correct identifications if the print is down low on the list.</p>
<h2>Implications</h2>
<p>While these reports and studies indicate a need for caution when relying on fingerprint examinations, they do not mean that police should stop using fingerprints. </p>
<p>Fingerprinting is an essential tool for investigating crime, and should continue to be used for this purpose. But steps need to be taken to limit the likelihood of future miscarriages of justice.</p>
<p>Everyone in the system has a role to play. Scientists need to conduct <a href="https://www.aaas.org/report/latent-fingerprint-examination">further research under realistic conditions</a>. </p>
<p>Police forces must <a href="https://www.justice.gov/archives/ncfs/page/file/641676/download">take steps</a> to minimise the risks of cognitive bias. For example, they should use <a href="https://www.ncbi.nlm.nih.gov/pubmed/23601722">context management procedures</a> to avoid exposing examiners to unnecessary contextual information. </p>
<p>Lawyers and judges must make sure that only scientifically valid opinions are <a href="http://law.unimelb.edu.au/__data/assets/pdf_file/0011/2494325/04-Edmond.pdf">given in court</a>, and that the value of fingerprint evidence is not overstated. Fingerprint examiners should make it clear that they are <a href="https://www.webarchive.org.uk/wayback/archive/20150428160106/http:/www.thefingerprintinquiryscotland.org.uk/inquiry/files/TheFingerprintInquiryReport_High_res.pdf">expressing an opinion and not a fact</a>. </p>
<p>And everyone should acknowledge that errors do occur in fingerprinting analysis, and have happened in the past.</p><img src="https://counter.theconversation.com/content/85534/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jamie Walvisch does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Fingerprinting is a valuable police tool for tracking down suspects, but it’s not perfect. However, we can reduce the risk of any mistaken identity if we work within the limits of fingerprinting.Jamie Walvisch, Lecturer, Monash UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/761982017-04-19T01:08:24Z2017-04-19T01:08:24ZNow who will push ahead on validating forensic science disciplines?<figure><img src="https://images.theconversation.com/files/165724/original/image-20170418-32713-191vm0u.jpg?ixlib=rb-1.1.0&rect=257%2C26%2C2945%2C2093&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">When lawyers submit forensic evidence in court, is there legit science to back it up?</span> <span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Rape-Kits/a609eaccb35e4d3989c46e1b5c178fe5/1/0">AP Photo/Pat Sullivan</a></span></figcaption></figure><p>Science and the law are not natural partners. Science seeks to advance our understanding of the natural world. The law is tasked with ensuring public safety and making sure justice is properly served. Over time, science became another tool available to the legal system to pursue those goals. </p>
<p>During recent years, though, problems with some aspects of forensic science have come to light. Examples include false convictions based on <a href="http://www.abajournal.com/magazine/article/long_held_beliefs_about_arson_science_have_been_debunked_after_decades_of_m">faulty fire scene and burn pattern analysis</a> and on <a href="https://www.themarshallproject.org/records/1001-bite-mark-evidence#.fvKzrjEIe">bite mark analysis</a>, <a href="https://oig.justice.gov/special/s0601/exec.pdf">incorrect fingerprint identification</a> and instances of <a href="https://www.bostonglobe.com/metro/2017/01/18/state-high-court-orders-prosecutors-drop-weak-dookhan-cases/SAvG09FT8lb6Mcv8cMMIKO/story.html">misconduct in forensic labs</a>. Recognizing these shortcoming has led to various efforts to propel forensic science forward, helping us recognize which parts of it are scientifically valid, which parts aren’t and where more research must be done.</p>
<p>This month, <a href="https://www.washingtonpost.com/local/public-safety/sessions-orders-justice-dept-to-end-forensic-science-commission-suspend-review-policy/2017/04/10/2dada0ca-1c96-11e7-9887-1a5314b56a08_story.html">Attorney General Jeff Sessions ended support</a> for the <a href="https://www.justice.gov/ncfs">National Commission on Forensic Science</a> (NCFS). This federal advisory board was charged with making recommendations “to enhance the practice and improve the reliability of forensic science.” Sessions didn’t renew the charter of this independent group, instead <a href="https://www.justice.gov/opa/pr/attorney-general-jeff-sessions-announces-new-initiatives-advance-forensic-science-and-help">announcing other steps</a> to be taken within the Department of Justice.</p>
<p>DOJ is not a science agency and thus not the ideal place to address core scientific issues. The department is staffed with dedicated public servants and exemplary forensic scientists, but the independence of science (real and perceived) remains a concern. The loss of the NCFS, of which I was a member, disrupts our work to help forensic science come of age and to insure the scientific validity of all its subdisciplines – a desirable outcome for its practitioners, the legal system and all of us who are served by it. </p>
<h2>Critical calls for more work</h2>
<p>A number of practices in forensic science require additional scientific scrutiny and validation. Indeed, any scientific method or practice requires periodic review and update to keep pace with developments in the field. </p>
<p>In 2009, the National Research Council published its “<a href="https://doi.org/10.17226/12589">Strengthening Forensic Science in the United States: A Path Forward</a>” report, which spelled out the discipline’s shortcomings and made numerous recommendations on how to improve and support it. These included creating an independent federal entity to address the many needs of the forensic science community including more research, assistance with accreditation and increasing scientific rigor. The report had the misfortune of being published during the Great Recession, when the appetite for creating a new federal entity was subdued at best.</p>
<p><a href="https://theconversation.com/forensic-evidence-largely-not-supported-by-sound-science-now-what-67413">Other efforts were launched</a> on smaller scales, one of which was the <a href="https://www.justice.gov/ncfs">National Commission on Forensic Science</a>, which met for the first time in February 2014. As a forensic chemist who works in academia, I was honored to serve on this body, which was jointly supported by the DOJ and the National Institutes of Standards and Technology (NIST).</p>
<p>The NCFS was the first national level group to bring together the <a href="https://www.justice.gov/ncfs/members">full range of stakeholders</a> in the forensic science universe: judges, lawyers (academic, prosecution and defense), victim advocates, law enforcement agencies, forensic laboratory directors, DOJ and NIST scientists, forensic practitioners and academic research scientists. Such breadth and depth of representation at the national level was unprecedented; these groups have sometimes been accused of talking past, rather than to, each other. For this group to come to <a href="https://www.justice.gov/ncfs/work-products-adopted-commission">consensus on more than 40 recommendation documents</a> attests to their hard work and dedication.</p>
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<a href="https://images.theconversation.com/files/165330/original/image-20170413-25870-841cdi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/165330/original/image-20170413-25870-841cdi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165330/original/image-20170413-25870-841cdi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165330/original/image-20170413-25870-841cdi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165330/original/image-20170413-25870-841cdi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165330/original/image-20170413-25870-841cdi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165330/original/image-20170413-25870-841cdi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165330/original/image-20170413-25870-841cdi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Science and the courts may weigh things differently.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/mikecogh/8035396680">Michael Coghlan</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<h2>Precedent versus progress</h2>
<p>Science advances via experimentation and observation, hypotheses, peer review and publication, collaborative research with students and testable theories. Science values – cherishes – progress and forward movement. What we know today may be proven wrong tomorrow – and that would be celebrated as innovation and progress.</p>
<p>If I dropped an apple and it soared upward to disappear into the clouds, Isaac Newton would be the first to say “Cool!” (or the 17th-century equivalent) right before he tried to replicate the experiment, worked to understand what happened, why, and to incorporate what he learned into a new and improved theory of gravity (a predictive model) that could be tested and revised again and again as the data dictated.</p>
<p>The law is a different beast. The American legal system utilizes the adversarial system: Both sides in a case present arguments as to the merits of their positions before the entity that will be settling the matter (the trier-of-fact such as a judge or jury).</p>
<p>Past decisions, known as precedent, are the foundation of this process; as science leans forward, the law leans backward. Of course this doesn’t mean the law is backward. As a philosophy, the law places a different measure and meaning on precedent than does science. To oversimplify, science builds on prior knowledge, while the courts defer to it.</p>
<h2>Forensic science’s evolution</h2>
<p><a href="http://www.forensicsciencesimplified.org">Forensic science as a field</a> has roots both in medicine and in law enforcement. Some subdisciplines emerged from academia; others followed the science track to enter forensic practice. Still others were developed to assist law enforcement. As the work evolved, it was law enforcement personnel who undertook many of the associated analyses and testimony.</p>
<p>Therein lies the source of much of the current controversy and concern. The forensic disciplines that weren’t born in the world of science didn’t from their inception go through the crucible of scientific methodology and review. This does not mean they aren’t useful or valid; however, they must be demonstrated as such. If put forth as scientific, these practices must pass scientific scrutiny in the present day.</p>
<p>As an example, <a href="https://www.ncjrs.gov/pdffiles1/nij/225333.pdf">fingerprints have been used for identification and legal purposes</a> since the early 1900s. The decision to admit fingerprints to court as evidence in 1911 was made based on the adversarial system and judicial arguments; it didn’t stem from scientific debate and certainly not from 21st-century scientific standards. Scientific scrutiny is an ongoing process, not something done once and settled. This applies to every forensic science practice, from DNA to pattern evidence. </p>
<p>Admissibility is not synonymous with scientific validity. Yet this distinction is not always made clear nor clearly understood by those involved with the court system. The validity of using <a href="https://obamawhitehouse.archives.gov/sites/default/files/microsites/ostp/PCAST/pcast_forensic_science_report_final.pdf#page=%5B96%5D">bite marks as identifiers has been debunked</a>. Yet <a href="https://www.washingtonpost.com/news/the-watch/wp/2017/01/30/incredibly-prosecutors-are-still-defending-bite-mark-evidence/?utm_term=.5a068796a028">some courts still admit such evidence</a>, and false convictions involving bite marks continue to be reversed, often because of DNA analysis. Without clear statements of the lack of scientific validity, admissibility often falls back on precedent. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/165722/original/image-20170418-32716-1tjowij.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/165722/original/image-20170418-32716-1tjowij.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165722/original/image-20170418-32716-1tjowij.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=452&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165722/original/image-20170418-32716-1tjowij.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=452&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165722/original/image-20170418-32716-1tjowij.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=452&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165722/original/image-20170418-32716-1tjowij.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=568&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165722/original/image-20170418-32716-1tjowij.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=568&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165722/original/image-20170418-32716-1tjowij.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=568&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Forensic evidence – as collected in a rape kit – can make or break a case.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Rape-Kits-Backlog/39a648d5e6c44758a9a06e4b3bab3d4d/2/0">AP Photo/Pat Sullivan</a></span>
</figcaption>
</figure>
<h2>Applying scientific standards to forensic science</h2>
<p>One of the goals of the National Commission on Forensic Science’s Scientific Inquiry Subcommittee, which I co-chaired, was to encourage and emphasize more work on scientific validation for the forensic disciplines. I don’t know a single forensic scientist true to her roots who has any problem or concern about independent assessment of the validity of her disciplines. This is the essence of being a scientist.</p>
<p>We also asked that the National Institutes of Standards and Technology evaluate these questions where needed. Doing so will provide the field with peer-reviewed literature spelling out what’s legitimate and what remains unsupported. We need clear statements of the scope and limits of forensic methods – known and understood by scientists, legal professionals and the public. Finally, we recommended that the term “to a reasonable degree of scientific certainty” no longer be used in reports and testimony. No one knows what that means, and it’s easy to imagine a judge or jury misconstruing such wording. </p>
<p>Understanding what forensic disciplines can and can’t do is vital information for any audience. To tell the truth, the whole truth and nothing but the truth demands that the strengths and limitations of any procedure and result be made known and understood.</p>
<p>Now that Sessions will not renew the NCFS, the progress being made in forensic science will slow, but it will not end. Due to the dedication of many unsung heroes in the forensic science community, progress has been made since the NRC report was published, and momentum has been established. For example, the need for universal accreditation of forensic laboratories at all levels is generally accepted by all parties as vital now, as was clear in multiple presentations at the <a href="https://www.justice.gov/ncfs/term-2-meetings-8-15">last meeting of the NCFS</a>. But accreditation is an arduous process that requires time and money, two things most forensic science labs do not have to spare. Without the necessary resources, it can’t happen despite best intentions. </p>
<p>NIST has become central to further progress in forensic science. It’s <a href="https://www.nist.gov/forensics/organization-scientific-area-committees-forensic-science">established committees to develop standards for forensic practice</a>; these groups do include independent researchers and academics, so that vital perspective is still being heard. However, there is concern by former commissioners that this enormous effort – by the community and by NIST – is in danger of losing vital funding and support. Ending the NCFS was a blow, but the loss of these committees and the wider participation of NIST and other scientists would be infinitely worse.</p>
<p>The 2009 NRC report, along with a <a href="https://obamawhitehouse.archives.gov/sites/default/files/microsites/ostp/PCAST/pcast_forensic_science_report_final.pdf">2016 report from the President’s Council of Advisors on Science and Technology</a>, is clear in this regard: the DOJ is not a science agency. Relying exclusively on the DOJ for reform is sort of like allowing admissibility based on precedent. Just because it was done this way in the past does not mean it’s the best way to do it now. We need a science agency – equally and completely free from both defense and prosecutorial pressures – to address the scientific issues in forensic science.</p><img src="https://counter.theconversation.com/content/76198/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Suzanne Bell receives funding from granting agencies including the National Institute of Justice and the National Institutes of Standards and Technology. The opinions expressed here are her own and not are not meant to represent opinions of any other entity or organization. </span></em></p>Forensics has a way to go before it’s a mature, academic science. Attorney General Jeff Sessions just terminated an independent commission charged with helping it get there.Suzanne Bell, Professor of Chemistry and Forensic and Investigative Science, West Virginia UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/674132016-12-07T02:09:16Z2016-12-07T02:09:16ZForensic evidence largely not supported by sound science – now what?<figure><img src="https://images.theconversation.com/files/148465/original/image-20161202-25663-91pf45.jpg?ixlib=rb-1.1.0&rect=205%2C195%2C3005%2C2198&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Is this worth the tape it's wrapped with?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/billselak/3086892145">Bill Selak</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Forensic science has become a mainstay of many a TV drama, and it’s just as important in real-life criminal trials. Drawing on biology, chemistry, genetics, medicine and psychology, forensic evidence helps answer questions in the legal system. Often, forensics provides the “smoking gun” that links a perpetrator to the crime and ultimately puts the bad guy in jail. </p>
<p>Shows like “CSI,” “Forensic Files” and “NCIS” cause viewers to be <a href="https://theconversation.com/the-csi-effect-are-jurors-starstruck-by-forensic-evidence-2066">more accepting</a> of <a href="https://apps.americanbar.org/litigation/committees/trialevidence/articles/winterspring2012-0512-csi-effect-jurors.html">forensic evidence</a>. As it’s risen to ubiquitous celebrity status, forensic science has become shrouded in a cloak of infallibility and certainty in the public’s imagination. It seems to provide definitive answers. Forensics feels scientific and impartial as a courtroom weighs a defendant’s possible guilt – looking for proof beyond a reasonable doubt.</p>
<p>But the faith the public and the criminal justice system place in forensic science far outpaces the amount of trust it deserves.</p>
<p><a href="http://doi.org/10.1146/annurev.lawsocsci.4.110707.172303">For decades</a>, there <a href="http://www.nij.gov/topics/forensics/lab-operations/capacity/nfsia/pages/welcome.aspx">have been concerns</a> about <a href="http://www.innocenceproject.org/u-s-department-of-justice-failing-to-enforce-critical-forensic-oversight-new-innocence-project-report-finds/">how the legal system uses forensic science</a>. A groundbreaking 2009 report from the National Academy of Sciences finally drew the curtain back to reveal that the wizardry of forensics was more art than science. <a href="https://www.nap.edu/catalog/12589/strengthening-forensic-science-in-the-united-states-a-path-forward">The report</a> assessed forensic science’s methods and developed recommendations to increase validity and reliability among many of its disciplines.</p>
<p>These became the catalyst that finally forced the federal government to devote serious resources <a href="https://www.nist.gov/news-events/news/2014/08/nist-establish-research-center-excellence-forensic-science">and dollars</a> to an effort to more firmly ground forensic disciplines in science. After that, governmental agencies, forensic science <a href="https://www.justice.gov/ncfs">committees</a> and even the <a href="http://www.cid.army.mil/dfsc-usacil.html">Department of Defense</a> responded to the call. Research to this end now receives approximately US$13.4 million per year, but the money may not be enough to prevent bad science from finding its way into courtrooms. </p>
<p>This fall, the President’s Council of Advisors on Science and Technology (<a href="https://www.whitehouse.gov/administration/eop/ostp/pcast">PCAST</a>) released its own <a href="https://www.whitehouse.gov/sites/default/files/microsites/ostp/PCAST/pcast_forensic_science_report_final.pdf">report on forensic science</a>. It’s a more pronounced acknowledgment that the discipline has serious problems that require urgent attention. Some scientific and legal groups are <a href="http://www.ndaa.org/pdf/NDAA%20Press%20Release%20on%20PCAST%20Report.pdf">outraged by</a> or <a href="https://www.fbi.gov/file-repository/fbi-pcast-response.pdf/view">doubtful of</a> its conclusions; others have <a href="https://www.nacdl.org/PCAST_Report/">praised</a> them. </p>
<p>As someone who has taught forensic evidence for a decade and dedicated my legal career to working on cases involving forensic science (both good and bad), I read the report as a call to address foundational issues within forensic disciplines and add oversight to the way forensic science is ultimately employed by the end user: the criminal justice system.</p>
<h2>Is any forensic science valid?</h2>
<p>The President’s Council of Advisors on Science and Technology <a href="https://www.whitehouse.gov/blog/2016/09/20/pcast-releases-report-forensic-science-criminal-courts">recognized ongoing efforts to improve forensic science</a> in the wake of the 2009 NAS report. Those efforts focused on policy, best practices and research around forensic science, but, as with any huge undertaking, there were gaps. As PCAST noted, forensic science has a validity problem that is in desperate need of attention. </p>
<p>PCAST focused on what’s colloquially termed “pattern identification evidence” – it requires an examiner to visually compare a crime scene sample to a known sample. PCAST’s big question: Are DNA analysis, bite marks, latent fingerprints, firearms identification and footwear analysis supported by reproducible research, and thus, reliable evidence?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/148467/original/image-20161202-25667-1mq2o5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/148467/original/image-20161202-25667-1mq2o5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/148467/original/image-20161202-25667-1mq2o5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=283&fit=crop&dpr=1 600w, https://images.theconversation.com/files/148467/original/image-20161202-25667-1mq2o5c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=283&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/148467/original/image-20161202-25667-1mq2o5c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=283&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/148467/original/image-20161202-25667-1mq2o5c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=356&fit=crop&dpr=1 754w, https://images.theconversation.com/files/148467/original/image-20161202-25667-1mq2o5c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=356&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/148467/original/image-20161202-25667-1mq2o5c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=356&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">What does a firing pin indentation on a bullet really tell us?</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/107963674@N07/20742290605">Macroscopic Solutions</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
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</figure>
<p>They were looking for two types of validity. According to PCAST, foundational validity means the forensic discipline is based on research and studies that are “repeatable, reproducible, and accurate,” and therefore reliable. The next step is applied validity, meaning the method is “reliably applied in practice.” In other words, for a forensic discipline to produce valid evidence for use in court, there must be (1) reproducible studies on its accuracy and (2) a method used by examiners that is reproducible and accurate.</p>
<p>Among the forensic science they assessed, PCAST found single-sourced DNA analysis to be the only discipline that was valid, both foundationally and as applied. They found DNA mixture evidence – when DNA from more than one person is in a sample, for instance from the victim and the perpetrator, multiple perpetrators or due to contamination – to be only foundationally valid. Same with fingerprint analysis. </p>
<p>Firearms identification had just the potential for foundational validity, but the research that could support it hasn’t been done yet. Footwear analysis lacked studies even showing potential for foundational validity. And bite mark analysis has a low chance of achieving any validity; the PCAST report advised “against devoting significant resources” to it.</p>
<p>All these types of evidence are widely used in thousands of trials each year. Many additional cases never even go to trial because this supposedly definitive evidence seems damning and compels defendants to plead guilty. But the lack of reliable science supporting these disciplines undermines the evidence which, in turn, undermines criminal convictions.</p>
<h2>Risks of lacking validity</h2>
<p>When forensic methods are not validated but nevertheless perceived as reliable, wrongful convictions happen.</p>
<p>For example, the field of forensic <a href="https://abfo.org/">odontology</a> presumes that everyone has a unique bite mark. But there’s no scientific basis for this assumption. A 2010 study of bite marks from known biters showed that skin deformations distort bite marks so severely that <a href="http://doi.org/10.1111/j.1556-4029.2010.01394.x">current methods of analysis could not accurately include or exclude a person</a> based on the pattern left by their teeth.</p>
<p>In 1986, Bennie Starks was convicted of rape and other crimes after forensic odontology experts testified he was the source of a bite mark on the victim. In 2006, DNA test results showed Starks could not have been the perpetrator. <a href="http://www.twincities.com/2013/08/30/correction-bite-mark-evidence-cases-story/">Starks spent 20 years in prison for a crime he did not commit</a> because of faulty evidence from an unreliable discipline. More recently, the Texas Forensic Science Commission recommended a flat-out <a href="http://blogs.wsj.com/law/2016/02/12/texas-commission-recommends-ban-on-bite-mark-evidence/">ban on bite mark evidence</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/148468/original/image-20161202-25663-xxdasi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/148468/original/image-20161202-25663-xxdasi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/148468/original/image-20161202-25663-xxdasi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/148468/original/image-20161202-25663-xxdasi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/148468/original/image-20161202-25663-xxdasi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/148468/original/image-20161202-25663-xxdasi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/148468/original/image-20161202-25663-xxdasi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/148468/original/image-20161202-25663-xxdasi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">What happens if the forensic evidence that convicted you is flimsy?</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/westmidlandspolice/7170656948">West Midlands Police</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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</figure>
<p>Like in Starks’ case, questionable forensic evidence plays a significant role in <a href="http://www.innocenceproject.org/causes/unvalidated-or-improper-for">at least half of overturned convictions</a>, according to the Innocence Project. Once a verdict comes in, it becomes a Sisyphean task to undo it – even if newly discovered evidence undermines the original conviction. It’s next to impossible for people once convicted to get their cases reconsidered.</p>
<p>At the moment, only two states (<a href="http://www.theatlantic.com/national/archive/2014/02/in-texas-a-new-law-lets-defendants-fight-bad-science/283895/">Texas</a> and <a href="http://blogs.mcgeorge.edu/lawandpolicy/wp-content/uploads/2014/09/SB-1058-False-Evidence.pdf">California</a>) permit a defendant to appeal a conviction if the scientific evidence or the expert who testified is later discredited. More laws like these are needed, but it’s politically a hard sell <a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=1559408">to grant more rights and avenues of appeal</a> to convicts. So even if the science is undermined or completely discredited, a prisoner is often at the mercy of a court as it decides whether to grant or deny an appeal. </p>
<h2>What should be admissible?</h2>
<p>The PCAST report recommended judges consider both the foundational and applied validity of the forensic discipline that produced any evidence before admitting expert testimony. This includes ensuring experts testify to the limitations of the analysis and evidence. For example, the justice system traditionally considers fingerprint evidence as an “identification” – for instance, the thumbprint recovered from the crime scene was made by the defendant’s thumb. No one ever testifies that there are <a href="http://doi.org/10.1093/lpr/mgm022">little scientific data</a> establishing that fingerprints are unique to individuals. The same holds true for other types of pattern identification evidence such as firearms, toolmarks and tire treads. </p>
<p>The National District Attorneys Association (NDAA) was <a href="http://www.ndaa.org/pdf/NDAA%20Press%20Release%20on%20PCAST%20Report.pdf">critical of the PCAST report</a>. It countered that there actually is scientific data validating these forensic fields, but members of PCAST did not adequately consult subject-matter experts. The NDAA also worried that if courts required stronger scientific validity before allowing evidence into court, it would hamstring the entire investigative process.</p>
<p>The NDAA concluded that judges should continue to be the ones who decide what makes evidence reliable and thus admissible. It asserted that the stringent requirements to become expert witnesses, along with the ability to cross-examine them in court, are enough to guarantee reliable and admissible evidence. </p>
<p>But should the admissibility of scientific processes – which ought to be grounded in their proven ability to produce reliable evidence – be determined by people who lack scientific backgrounds? I would argue no. </p>
<p>Pattern identification evidence shouldn’t be excluded from cases wholesale, but forensic evidence needs to be placed into context. When the human eye is the primary instrument of analysis, the court, the attorneys and the jury should be fully aware that certainty is unattainable, human error is possible, and subjectivity is inherent.</p>
<p>Reliance upon the adversary system to prevent wrongful convictions and weed out junk science requires a leap of faith that ultimately undermines the integrity of the criminal justice system. Counting on cross-examination as an effective substitute for scientific rigor and research can’t be the answer (although it has been for more than a century).</p>
<p>The PCAST report is yet another wake-up call for the criminal justice system to correct the shortcomings of forensic science. We demand that guilt be proven beyond a reasonable doubt; we should also demand accurate and reliable forensics. Without improvement, we can’t trust forensic science to promote justice.</p><img src="https://counter.theconversation.com/content/67413/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jessica Gabel Cino has received a grant from Georgia Institute of Technology to examine wrongful convictions (2010). She also serves on the American Academy of Forensic Science's Standards Boards for DNA and fingerprints.</span></em></p>Is forensic science an oxymoron? A new White House report suggests there are major issues with many of the forensic disciplines used to convict defendants of crimes in the U.S.Jessica Gabel Cino, Associate Dean for Academic Affairs and Associate Professor of Law, Georgia State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/659552016-09-28T04:23:31Z2016-09-28T04:23:31ZThere are question marks over much of the forensic evidence used in our courts<figure><img src="https://images.theconversation.com/files/139522/original/image-20160928-716-1rgrv0u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tread carefully when relying on forensic footwear evidence.</span> <span class="attribution"><span class="source">kilukilu/Shutterstock.com</span></span></figcaption></figure><p>Crime dramas in film and television often focus on the value of forensic procedures in solving crimes and convicting criminals. While this evidence is often portrayed as almost infallible, a <a href="https://www.whitehouse.gov/blog/2016/09/20/pcast-releases-report-forensic-science-criminal-courts">report released this month in the United States</a> raises significant doubts.</p>
<p>The President’s Council of Advisors on Science and Technology (<a href="https://www.whitehouse.gov/administration/eop/ostp/pcast">PCAST</a>) concluded that many commonly used forensic procedures lack adequate scientific validation. The procedures include things such as bite-mark analysis, microscopic hair comparisons, firearms identification and footwear analysis.</p>
<p>The report says there is insufficient research that establishes the accuracy and consistency of these procedures. </p>
<p>Given that this forensic evidence is used in criminal trials in Australia, the report’s findings are relevant here, too. </p>
<p>The problems associated with this sort of evidence are most clearly illustrated in relation to a form of forensic evidence of which PCAST was particularly critical: bite-mark identification.</p>
<h2>What is bite-mark identification?</h2>
<p>This process usually involves comparing a record of bite marks made by an accused’s teeth with a record of a bite mark left on a victim.</p>
<p>Police sometimes use this form of analysis to identify an offender where a victim has been bitten but the prosecution cannot otherwise identify the offender. This could be in cases where the victim did not see or hear the offender, or in a homicide because the victim is dead.</p>
<p>The <a href="https://www.washingtonpost.com/news/the-watch/wp/2015/02/17/it-literally-started-with-a-witch-hunt-a-history-of-bite-mark-evidence/?utm_term=.7d098ab95317">use of bite marks</a> for the purpose of identifying offenders has a long history. It was used in the Salem witch trials in 1692 to convict Reverend George Burroughs of witchcraft after his teeth were matched with bite marks on a victim. The case provides a warning: Burroughs was <a href="http://law2.umkc.edu/faculty/projects/ftrials/salem/SAL_BBUR.HTM">posthumously exonerated and his family compensated</a> for his wrongful conviction and death.</p>
<p>More recently, cases in 20th-century America have seen bite-mark evidence used to help obtain convictions, including that of <a href="http://www.biography.com/people/ted-bundy-9231165">serial killer Ted Bundy</a>.</p>
<p>But there is increasing concern about how this identification is done and how accurate it really is. These concerns are highlighted in cases of wrongful convictions.</p>
<h2>Wrongful convictions</h2>
<p>In several cases in the United States, individuals have had their convictions overturned because they were wrongfully convicted on the basis of bite-mark evidence. </p>
<p>In 1992, <a href="http://www.innocenceproject.org/cases/ray-krone/">Ray Krone</a> was convicted of murder and sentenced to death, largely on the basis of evidence that matched his teeth to a bite mark on the deceased.</p>
<p>He spent ten years in prison before he was released. His exoneration occurred after DNA on the victim’s clothes was matched to another offender. </p>
<p>More recently, <a href="http://www.innocenceproject.org/dallas-district-attorney-and-innocence-project-move-to-reverse-conviction-based-on-false-bite-mark-testimony/">Stephen Chaney was released</a> after spending 28 years in prison following his conviction for a double murder in Texas.</p>
<p>At Chaney’s original trial an expert told the jury there was a “<a href="http://innocenceproject.olemiss.edu/bite-mark-evidence-flaws-produces-another-exoneration/">one to a million</a>” chance that someone other than Chaney had bitten the victim. But by 2015 that expert had recanted his testimony and the prosecution acknowledged that the bite-mark evidence was unreliable. </p>
<h2>Bite-mark evidence in Australia</h2>
<p>Identification based on bite-mark evidence appears to be relatively rare in Australia but it certainly has its supporters. The Australian Federal Police <a href="http://www.australianpolice.com.au/forensic-scientists/forensic-odontology/">approvingly notes on its website</a> a case in which bite-mark evidence was crucial:</p>
<blockquote>
<p>A sex-attacker punched his victim and then threatened to kill her. In the struggle he bit her on the breast. A forensic odontologist took an impression of the bite mark which later convinced a jury that the accused was, indeed, the attacker. He was convicted and sentenced accordingly.</p>
</blockquote>
<p>Bite-mark evidence was also tendered in one of Australia’s most controversial criminal cases: the trial of <a href="http://www.qt.com.au/news/murder-that-stole-ipswichs-innocence-innocence/1819762/">Raymond Carroll</a> for the murder of an infant in Ipswich in 1973.</p>
<p>A post-mortem examination had revealed bruising on the infant’s thigh. Although an initial investigation concluded that it would not be possible to identify an offender on the basis of these marks, three forensic dentists subsequently testified at Carroll’s trial in 1985 that the bruising was caused by biting and that the mark matched Carroll’s teeth.</p>
<p>These experts also acknowledged the difficulties of bite-mark identification. Carroll was convicted of the murder. </p>
<p>But the Queensland Court of Appeal was sensitive to the problems associated with bite-mark evidence. It <a href="http://www.austlii.edu.au/cgi-bin/sinodisp/au/cases/qld/QCA/2001/394.html?stem=0&synonyms=0&query=bite-mark">subsequently overturned Carroll’s conviction</a> on the basis that the evidence did not provide a reliable basis on which he could have been found guilty beyond reasonable doubt.</p>
<h2>Unreliable evidence</h2>
<p>Predictably, police and prosecutors have <a href="https://www.fbi.gov/file-repository/fbi-pcast-response.pdf/view">condemned</a> attempts to restrict reliance on forensic evidence. They claim that this will hamper crime investigation and deprive them of valuable means of identifying offenders. </p>
<p>But identifications based on scientific procedures that have not been properly validated carry a high risk of causing miscarriages of justice. </p>
<p>PCAST has recommended that further research be conducted to consolidate the scientific bases of forensic procedures such as DNA and latent fingerprint analysis. </p>
<p>However, the commission found that the prospect of developing bite-mark analysis into a scientifically valid method was so low that it advised against devoting significant resources to the task. </p>
<p>Clearly, we must be more discerning in the types of forensic science we admit into courts. The reservations expressed by the appellate court in Carroll’s case should be extended. Until research establishes bite-mark analysis (or any other forensic technique) as a valid and reliable procedure, identifications based on this type of evidence should not be admitted in criminal trials in Australia.</p><img src="https://counter.theconversation.com/content/65955/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Marilyn McMahon does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A US report has cast doubt on a range of techniques commonly used to secure criminal convictions, such as identification using bite marks, hair strands or footwear.Marilyn McMahon, Associate Professor in Law, Deakin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/650632016-09-13T13:00:50Z2016-09-13T13:00:50ZPlastic banknotes: new fingerprint technique means criminals can’t avoid capture<p>The UK has just <a href="http://www.bankofengland.co.uk/banknotes/polymer/Pages/default.aspx">introduced plastic banknotes</a>, almost 30 years after they were used for the first time in Australia. The polymer notes are designed to last longer and be harder to forge. But the new notes, which will replace the old cotton paper ones entirely by 2020, come with a challenge for police detectives and forensic scientists.</p>
<p>The existing techniques for obtaining fingerprints from paper notes won’t necessarily work for the new plastic money. However, our team at the chemistry department of Loughborough University has developed a potential solution.</p>
<p>The use of fingerprints in forensic science may <a href="http://www.onin.com/fp/fphistory.html">date back to the 19th century</a>, but in the UK alone it still plays a key role in bringing charges in some 27,000 crimes a year, according to Home Office data we obtained. But new materials can pose significant challenges for fingerprinting. We’re forever trying to make things biodegradable, or handling devices that simply didn’t exist a decade or two ago.</p>
<p>The issue is that the new notes have been fashioned from <a href="http://www.packworld.com/material-type/polymers/understanding-biaxially-and-monaxially-oriented-films">“biaxially oriented” polypropylene</a>, a type of plastic that has been strengthened by stretching it in two directions. They are also, as with all notes, deliberately fiddly in design. Illustrations and security features such as foil and transparent sections make it harder to develop a perfect print.</p>
<p>The key is to try to find a method that will make the design of the note invisible and just highlight the print. Conventional techniques, such as exposing the fingerprint to <a href="https://dps.mn.gov/divisions/bca/bca-divisions/forensic-science/Pages/forensic-programs-crime-scene-superglue.aspx">cyanoacrylate (“superglue”) fumes</a> that stick to the moisture in the ridges of the print and turn them white, can struggle in such circumstances. The developed print simply appears white and so is harder to see against the background, and it leaves an indelible mark or stain that means the note can’t be returned to circulation.</p>
<p>To overcome these various problems, we combined several techniques for revealing and capturing fingerprints that together can be used to successfully retrieve prints from plastic notes. This involves placing a thin layer of copper over the note that helps reveal the prints when illuminated with light of a certain wavelength, rendering the background of the note effectively invisible. You can also then cover the note in a forensic gel, which is usually used to <a href="https://www.gov.uk/government/uploads/system/uploads/atta_chment_data/file/512189/fingerprint-footwear-forensics-feb2010.pdf">retrieve footprints and similar marks at crime scenes</a>. The gel is then peeled off and treated to reveal and preserve the prints.</p>
<p>The process relies on a technique known as vacuum metal deposition, <a href="http://www.west-technology.co.uk/vmd360-fingerprint-vacuum-metal-deposition-system.asp">VMD</a>. This involves placing the sample in a high-vacuum chamber and then heating copper wire until it effectively boils. The resulting vapour is then allowed to condense in a layer of precisely defined thickness.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/137551/original/image-20160913-19258-etedm8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/137551/original/image-20160913-19258-etedm8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=463&fit=crop&dpr=1 600w, https://images.theconversation.com/files/137551/original/image-20160913-19258-etedm8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=463&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/137551/original/image-20160913-19258-etedm8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=463&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/137551/original/image-20160913-19258-etedm8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=582&fit=crop&dpr=1 754w, https://images.theconversation.com/files/137551/original/image-20160913-19258-etedm8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=582&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/137551/original/image-20160913-19258-etedm8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=582&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Revealing the prints.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Once the copper is in place, the note is illuminated with light of many different wavelengths. To the naked eye the results appear underwhelming. But if filters are used to just let near infra-red wavelengths through, then the prints are revealed against an almost invisible background.</p>
<p>We now need to test whether the technique can work on notes that have been through the washing machine or degraded over time. Predicting just how this would change surface interaction with prints is not so easy. But our method combines two technologies (VMD and imaging systems) that are already well established in forensic circles.</p>
<p>The added bonus is that an invisible layer of copper just a few nanometres thick wouldn’t damage the notes and they could easily be returned to circulation. So forensic scientists should be able to start gathering evidence from the new plastic notes right away, without having to put their impressive durability to the test.</p><img src="https://counter.theconversation.com/content/65063/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paul Kelly worked alongside forensic instrument manufacturers Foster & Freeman and West Technology Systems in a collaborative venture for this study.</span></em></p>New plastic banknotes pose a challenge to forensic scientists that clever chemistry can solve.Paul Kelly, Reader, Loughborough UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/481812015-09-29T14:01:37Z2015-09-29T14:01:37ZRomanov mystery: can digging up 100-year-old bodies help crack unsolved murders?<figure><img src="https://images.theconversation.com/files/96647/original/image-20150929-30993-29eppu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Wikimedia Commons</span></span></figcaption></figure><p>Imagine the untold misery caused by telling the wrong family that their loved one is dead while another family is left in blissful ignorance. That’s why accurately identifying bodies is of paramount importance.</p>
<p>Identification is usually based on simple criteria. Visual recognition or distinctive tattoos are often enough. But as time passes and the body deteriorates, these methods become less reliable or impossible. This will certainly be the case for the bodies alleged to be those of Russia’s Crown Prince Alexei and Grand Duchess Maria, which are <a href="http://www.theguardian.com/world/2015/sep/23/russia-tests-romanov-royal-family-remains">due to be re-examined</a> in an attempt to determine if they are the real royals killed during the Russian Revolution.</p>
<p>Forensic analysis has developed apace in the last century, and DNA technology in particular has opened ways of analysing bodies that were previously unthought of even relatively recently. Such technology is increasingly being applied to cases from the past, and the media are always <a href="http://news.nationalgeographic.com/news/2005/02/0210_020510_tv_witchcraft.html">quick to report stories</a> where high profile mysteries are finally “solved” using modern forensics. The cynic would note that some cases (I’m particularly thinking of the “Jack the Ripper” murders) have been “definitively solved” <a href="https://theconversation.com/still-a-mystery-dna-hasnt-named-jack-the-ripper-after-all-33312">several times</a> with <a href="http://www.telegraph.co.uk/news/uknews/crime/11771381/Jack-the-Ripper-identity-mystery-solved-in-new-book.html">different outcomes</a>.</p>
<h2>DNA evidence</h2>
<p>So what can forensic science actually bring to these old cases? Certainly DNA can often be extracted from the body, often in teeth and bones. But a DNA profile isn’t just a printout of who someone is. It has to be compared to a known profile. It’s unlikely that we still have a hairbrush or toothbrush from Crown Prince Alexei, but if we have a known sample of DNA from a relation (such a bloodstains on a uniform from his great-grandfather Emperor Alexander II) then familial similarities <a href="https://www.fbi.gov/about-us/lab/biometric-analysis/codis/familial-searching">can be used</a>.</p>
<p>Our knowledge of DNA can do more than just identify someone. An old DNA sample can spot any <a href="http://news.sciencemag.org/biology/2009/10/case-closed-famous-royals-suffered-hemophilia">genetic diseases</a> a subject may have been prone to. Similarly, advances in technology allow us to look at the <a href="http://pubs.rsc.org/en/Content/ArticleLanding/2012/AY/C2AY25035G#!divAbstract">chemical composition</a> of bones and determine what kinds of things they ate and so where in the world they probably came from.</p>
<p>Analysis of pollen from the sinuses can tell us about what plants were around the person. <a href="https://theconversation.com/explainer-what-is-radiocarbon-dating-and-how-does-it-work-9690">Carbon dating</a> may tell us how old someone actually is, although – as with most forensic techniques – only a range of dates can be given rather than a definitive answer. All of this information can help us work out whose body is (or isn’t) being examined.</p>
<p>But we also shouldn’t forget the simpler techniques. Just looking at a body may yield information depending on how well it has been preserved. Old or perimortem (from the time of death) injuries or bone deformities may be apparent. The shape of the skull and teeth may point to gender and ethnicity. CT scanning can show us inside the body without having to open it, helpful when dissection, which is an invasive and destructive process, is <a href="https://www.britishmuseum.org/explore/online_tours/egypt/mummy_the_inside_story/mummy_the_inside_story.aspx">not an option</a>.</p>
<p>This battery of tests can tell us an awful lot about how someone lived, how they died, and who they may have been. The most publicised example of this in the UK was the discovery of <a href="https://theconversation.com/nine-blows-to-the-head-and-then-he-was-dead-forensics-shed-light-on-killing-of-richard-iii-31751">King Richard III</a>, which was identified by my colleagues at Leicester University last year.</p>
<p>It’s not just the body itself that the forensic investigators can examine. If someone is buried, what is the grave like – deep or shallow? What does the soil tell us? If the body is in a shroud, how was that made and of what? The possibilities are only limited by the imagination of the investigators. </p>
<h2>Unsolved mysteries</h2>
<p>But before we get carried away, we must bear in mind that few things in this field are completely certain. By way of example, you’d think that attempts to carbon date the <a href="http://www.theguardian.com/world/2015/apr/19/turin-shroud-on-display-for-first-time-in-five-years">Shroud of Turin</a> – the cloth claimed to have covered Jesus’s dead body – would allow us to finally decide whether or not it really dates to Biblical times. But when the results came out suggesting not, an <a href="http://news.bbc.co.uk/1/hi/sci/tech/4210369.stm">argument arose</a> as to whether the sample tested was from the original weave or part of a medieval repair.</p>
<p>As time passes, the possibility of deterioration, contamination, alteration or outright fraud of a sample increases. The more people who handle a body, the more foreign DNA can be introduced. Time changes the body and changes the environment.</p>
<p>Finally, there is always the issue of interpretation. For example, was Palestinian leader Yasser Arafat <a href="http://www.bbc.co.uk/news/world-middle-east-20512259">poisoned with radiation</a> or not? Different interpretations of the test results can lead to different conclusions. It was originally suggested that Arafat had been poisoned by 210 Polonium, and an exhumation of his body <a href="http://articles.latimes.com/2013/nov/06/world/la-fg-wn-arafat-death-polonium-20131106">produced samples</a> showing unusually high levels of this element, but <a href="http://www.theguardian.com/world/2013/dec/26/scientists-yasser-arafat-poisoned">later analysis</a> suggested that this was environmental in nature.</p>
<p>So can modern forensic science reveal secrets from the past? Yes, but not necessarily as definitively as excited headlines may wish us to believe.</p><img src="https://counter.theconversation.com/content/48181/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Stuart Hamilton does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Bodies thought to belong to members of Russia’s murdered royal family are to be re-examined for new evidence but forensics has its potential and limitations.Stuart Hamilton, Honorary Senior Clinical Teaching Fellow, University of LeicesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/457552015-08-10T10:12:33Z2015-08-10T10:12:33ZThere’s no code of ethics to govern digital forensics – and we need one<figure><img src="https://images.theconversation.com/files/91182/original/image-20150807-27617-trltku.jpg?ixlib=rb-1.1.0&rect=122%2C0%2C758%2C567&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">How to deal with all that digital evidence?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/westmidlandspolice/8102352763">West Midlands Police</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Let me begin with a disclaimer: I am neither a digital forensics practitioner nor do I play one on television. </p>
<p>I am, however, a professor in, and former chair of, an academic <a href="http://www.uab.edu/justice-sciences">department</a> at a research university that houses a graduate program in computer (digital) forensics I helped design. In 2011, I cofounded a computer forensics <a href="http://thecenter.uab.edu">research center</a> at my university. Finally, for more than 10 years, I have taught undergraduate and graduate courses on professional ethics for criminal justice and digital forensics students.</p>
<p>These experiences helped me to identify a glaring issue in the field of digital forensics: a lack of professional and ethical standards governing practitioners. And as digital forensics gains prominence in the legal landscape, the lack of agreed-upon standards is a big problem.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/91183/original/image-20150807-27582-xhg07m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/91183/original/image-20150807-27582-xhg07m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/91183/original/image-20150807-27582-xhg07m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/91183/original/image-20150807-27582-xhg07m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/91183/original/image-20150807-27582-xhg07m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/91183/original/image-20150807-27582-xhg07m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/91183/original/image-20150807-27582-xhg07m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/91183/original/image-20150807-27582-xhg07m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This way please.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/irinaslutsky/3481605062">irina slutsky</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>What <em>is</em> digital forensics?</h2>
<p>Digital or computer forensics involves the identification, recovery, analysis and presentation in court of relevant information taken from electronic devices such as computers and cellphones. </p>
<p>That information becomes <a href="http://www.rand.org/content/dam/rand/pubs/research_reports/RR800/RR890/RAND_RR890.pdf">digital evidence</a> presented in court and designed to tie together people and events in time and space to establish causality for crimes or civil wrongs. </p>
<p>For example, imagine the police arrested a suspect on charges she murdered her husband by poisoning him. The police will seize and examine the suspect’s computer to uncover incriminating evidence such as the suspect’s history of visiting web pages that deal with poisons. Once retrieved, the prosecutor will likely introduce that evidence to gain a conviction.</p>
<p>Digital evidence is not trivial. If it leads to a conviction on criminal charges, the defendant may face prison time. In a civil case, it can lead to a defendant having to pay monetary damages. And the police officers, technicians and private contractors who testify in court about digital evidence can be the difference between justice served and justice denied.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/91184/original/image-20150807-27587-1dma3vg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/91184/original/image-20150807-27587-1dma3vg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/91184/original/image-20150807-27587-1dma3vg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/91184/original/image-20150807-27587-1dma3vg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/91184/original/image-20150807-27587-1dma3vg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/91184/original/image-20150807-27587-1dma3vg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/91184/original/image-20150807-27587-1dma3vg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/91184/original/image-20150807-27587-1dma3vg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">It’s less obvious how to properly collect evidence from within the phone.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/westmidlandspolice/7131876629">West Midlands Police</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>The “Wild West” of digital forensics</h2>
<p>In some ways, the <a href="https://books.google.com/books?hl=en&lr=&id=lUnMz_WDJ8AC&oi=fnd&pg=PP1&dq=digital+forensics+training+and+practice&ots=aJr8JkDOU7&sig=vjAo6jeTmN2F48Z_sL1rGvLz598#v=onepage&q=digital%20forensics%20training%20and%20practice&f=false">digital forensics landscape</a> resembles the “Wild West.” At least part of the reason for this is that digital forensics is not science-driven; instead, it is driven by its practitioners.</p>
<p>Those involved with determining the relevance of digital evidence are sometimes <a href="https://ballinyourcourt.wordpress.com/2014/03/03/becoming-a-better-digital-forensics-witness/">ill-equipped</a> to make such assessments. </p>
<p><a href="https://www.ncjrs.gov/pdffiles1/nij/213420.pdf">Problems</a>, including inadequate training, use of outdated equipment, limited resources, few personnel and lack of a standardized protocol for analyzing digital evidence have all been documented. These shortcomings have led to evidentiary issues, improper conclusions by juries about digital evidence and doubtful outcomes. A good example would be the <a href="http://www.nytimes.com/2011/07/19/us/19casey.html?ref=topics&_r=0">Casey Anthony</a> trial, where improper analysis of her visits to websites dealing with murder was admitted as evidence. </p>
<p>Unlike DNA <a href="http://nij.gov/topics/forensics/evidence/dna/basics/pages/analyzing.aspx">analysis</a>, there’s no standardized protocol for identifying, recovering, or processing digital evidence. As a result, two different technicians at different crime labs might reach <a href="http://arxiv.org/ftp/arxiv/papers/1303/1303.4498.pdf">different conclusions</a> about a particular piece of evidence because they used different equipment or had divergent training. </p>
<p>These problems have implications for justice being served. </p>
<h2>First steps toward standards</h2>
<p>Thankfully, the situation is changing as the National Institute of Standards and Technology (<a href="http://www.nist.gov">NIST</a>) works to develop <a href="http://www.nist.gov/oles/forensics/digital_evidence.cfm">specific standards</a> for analyzing digital evidence. </p>
<p>The courts have also begun paying attention to some of the legal issues involving digital evidence. For example, in <a href="http://www.supremecourt.gov/opinions/13pdf/13-132_8l9c.pdf">Riley v California</a>, the US Supreme Court ruled in 2014 that police must obtain a search warrant before they can seize electronic devices suspected of containing digital evidence. This ruling makes it somewhat harder for police to seize and analyze personal devices involved in crimes. </p>
<h2>Lack of a code of ethics for practitioners</h2>
<p>Because the people who recover, analyze, process and testify about digital evidence are influential in court proceedings, they must be ethical in their dealings with the legal system. </p>
<p>However, the reality is this: not only is digital forensics the “Wild West” when it comes to protocols for processing evidence, there isn’t a code of ethics that governs the professional behavior of digital forensics practitioners. </p>
<p>Instead, various <a href="http://www.dfcsc.uri.edu/resources/centers_organizations">professional associations</a> have created a hodgepodge of codes of ethics for members. Some of them are <a href="https://www.dfcb.org/DFCB_DFCB_Code_of_Ethics_and_Standards_of_Professional_Conduct_Version_1.1_Dec08.pdf">very detailed</a>; others, <a href="http://digital-forensics.sans.org/certification/ethics">not so much</a>.</p>
<p>Unlike <a href="http://www.ama-assn.org/ama/pub/physician-resources/medical-ethics/code-medical-ethics.page">medicine</a> or <a href="http://www.americanbar.org/content/dam/aba/migrated/cpr/mrpc/mcpr.authcheckdam.pdf">law</a>, each of which has a single, overarching code of professional ethics enforced by the states, there is no comparable code that describes how a digital forensics practitioner should (or must) behave in his or her professional life.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/91185/original/image-20150807-27582-fr0a5a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/91185/original/image-20150807-27582-fr0a5a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/91185/original/image-20150807-27582-fr0a5a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=475&fit=crop&dpr=1 600w, https://images.theconversation.com/files/91185/original/image-20150807-27582-fr0a5a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=475&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/91185/original/image-20150807-27582-fr0a5a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=475&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/91185/original/image-20150807-27582-fr0a5a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=596&fit=crop&dpr=1 754w, https://images.theconversation.com/files/91185/original/image-20150807-27582-fr0a5a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=596&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/91185/original/image-20150807-27582-fr0a5a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=596&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Looking for uniform, ethical standards for digital evidence.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/joncrel/3213995470">jon crel</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>The challenge of creating a code of ethics</h2>
<p>Last May, I co-organized a two-day workshop on professional ethics and digital forensics that was funded by, and held at, the National Science Foundation (<a href="http://www.nsf.gov/">NSF</a>). Academics, researchers and practitioners attended. </p>
<p>The workshop explored the need for a code of ethics and the contours of what such a code might include. We also examined hurdles to establishing a code, and existing codes from other <a href="https://www.acm.org/about/code-of-ethics">professions</a> that could serve as models. </p>
<p>The consensus among participants was that the <a href="http://www.forensicmag.com/articles/2014/03/professional-ethics-digital-forensics-discipline-part-1">need is great</a> for a code of professional ethics that governs digital forensics practitioners. Participants shared examples of ethical issues that cloud the profession. Conflicts of interest. Vendors producing research on their own products and using that to influence agencies to adopt their product(s). Some practitioners’ lack of understanding of the mechanics of the software they use to process evidence (the “black box” problem). </p>
<p>However, just because participants agree a code of ethics is needed doesn’t mean there aren’t significant hurdles to overcome with creating one. What specific behavior would be covered? What themes would the code address (for instance, “fairness,” “trust,” “justice”)? What agency or organization would enforce the code? (Suggestions included NIST or the American Academy of Forensic Sciences (<a href="http://aafs.org/about/committees/ethics-committee">AAFS</a>).) To whom would the code apply? All practitioners involved with digital evidence or just those processing it?</p>
<h2>Moving forward</h2>
<p>To raise awareness and continue working to create a code of ethics, this academic year we plan to replicate the workshop at various professional meetings including those of the <a href="http://www.scja.net/">Southern Criminal Justice Association</a>, AAFS and the <a href="http://acjs.org/">Academy of Criminal Justice Sciences</a>. </p>
<p>We will also reach out to leaders in the AAFS and the <a href="http://www.americanbar.org/groups/departments_offices/legal_technology_resources/resources.html">American Bar Association</a> for help with developing the code.</p>
<p>As digital evidence becomes more common in legal proceedings, ensuring that practitioners have the strongest professional ethics is not only sensible, it is imperative.</p><img src="https://counter.theconversation.com/content/45755/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John J Sloan, III receives funding from the National Science Foundation (NSF). He is affiliated with the American Society of Criminology (ASC) and the Southern Criminal Justice Association (SCJA).</span></em></p>So much of modern life involves our digital devices – including crime. As the field of digital forensics gains prominence, practitioners need practical and ethical guidelines.John J. Sloan III, Professor of Criminal Justice and Sociology , University of Alabama at BirminghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/392302015-04-02T05:29:01Z2015-04-02T05:29:01ZForensic evidence offers only probabilities, not guarantees that justice will be served<figure><img src="https://images.theconversation.com/files/76670/original/image-20150331-1249-53uxf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">This is science, not clairvoyance.</span> <span class="attribution"><span class="source">fingerprint by Torsak Thammachote/www.shutterstock.com</span></span></figcaption></figure><p>Scientific evidence and expert witness testimony are integral to criminal trials worldwide. Yet while we live in a scientific age of increasingly specialised expert knowledge, a growing reliance on forensic evidence is a double-edged sword.</p>
<p>There is no doubting that forensic science techniques provide near-miraculous abilities to detect, investigate and prosecute crime. But any powerful medicine can have strong side-effects, if administered in excessive dosages or to the wrong patients. Forensic scientific evidence has won for itself an aura of credibility that verges on infallibility. This leaves flawed expert evidence as a potent source of potential injustice.</p>
<p>Is forensic science evidence fit for justice? Science and technology constantly evolve; forensic tests become ever more discriminating, cheaper and easier to use, and more freely available to law enforcement. Courts and legislators must not be complacent if they are to keep pace with scientific innovation. Unfortunately austerity-blighted Britain may be storing up serious trouble for the future.</p>
<h2>Forensics and miscarriages of justice</h2>
<p>It shouldn’t surprise us that forensic science is associated with miscarriages of justice. All forms of judicial evidence are inherently fallible: witnesses are sometimes dissembling or forgetful, or sincere and credible yet wrong. Confessions may be false or made under duress. As reliance on scientific evidence grows so too will the number of miscarriages of justice that stem from forensic science. It’s also fair to say that injustice occurs when the scientific evidence and techniques available are not exploited to their maximum. Scientific evidence is in some areas peculiarly vulnerable to unreliability and misinterpretation.</p>
<p>To begin with, scientific evidence is circumstantial. It may constitute strong evidence of the offender’s identity, his presence at the crime scene, or association with incriminating objects such as the murder weapon or stolen property. But it has at best very little, and generally no value in proving other elements of criminal liability such as intent, grounds of excuse, justification, or the absence of the victim’s consent. In other words, it typically leaves considerable scope for interpretation. </p>
<p>Scientific samples are prone to degradation and contamination, as demonstrated by recent high-profile cases <a href="http://www.bbc.co.uk/news/uk-19782917">in the UK</a> and <a href="http://www.smh.com.au/national/dna-fiasco-rape-conviction-quashed-20091207-kfc3.html">Australia</a> in which contaminated samples falsely incriminated innocents. Presented in court, there is a constant danger that it will be misrepresented or misunderstood by lawyers, judges, or jurors. These difficulties are compounded whenever scientific evidence offered by one legal team is contradicted, or given a different interpretation, by counter-expertise advanced by the opposing side.</p>
<p>There will always be a risk of error, attributable to human fallibility, that must be accepted regardless of our efforts to detect miscarriages of justice. But one aspect of modern forensic science evidence is genuinely novel. Starting with the <a href="http://www.crimescene-forensics.com/History_of_Fingerprints.html">invention of fingerprinting</a> about a century ago, forensic science has operated on the basis that it is possible to identify suspects or physical objects uniquely – an exclusively “matching” fingerprint, tool mark, hair sample, carpet fibre, bite mark would indicate the particular offender (or murder weapon, location of fibres or whatever). But the <a href="http://www2.le.ac.uk/study/why-us/discoveries/the-invention-of-dna-fingerprinting">arrival of DNA profiling</a> in the mid-1980s has seriously disrupted this way of thinking.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/76671/original/image-20150331-1253-lxkdg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/76671/original/image-20150331-1253-lxkdg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/76671/original/image-20150331-1253-lxkdg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/76671/original/image-20150331-1253-lxkdg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/76671/original/image-20150331-1253-lxkdg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/76671/original/image-20150331-1253-lxkdg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=490&fit=crop&dpr=1 754w, https://images.theconversation.com/files/76671/original/image-20150331-1253-lxkdg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=490&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/76671/original/image-20150331-1253-lxkdg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=490&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">DNA evidence is powerful, but should redefine how we think about evidence.</span>
<span class="attribution"><span class="source">DNA by The Biochemist Artist/www.shutterstock.com</span></span>
</figcaption>
</figure>
<h2>DNA profiles</h2>
<p>DNA profiles, derived from only small samples of a person’s entire genetic code, do not claim to point the finger so uniquely. They are statements of <a href="http://dna-view.com/profile.htm">random match probability</a> (RMP), the probability that a person would match the DNA at the crime scene? if they were not its donor. The conventional RMP for fully matching DNA profiles in England and Wales has been one in a billion – a tiny probability, but one which concedes the possibility that DNA profiles are not unique.</p>
<p>It was soon realised that, far from a weakness of DNA profiling in contrast to other well-established techniques, in fact DNA profiling represents a truly scientific approach, whereas orthodox forensic practice rested on a fallacy. It is never possible to conclusively identify a person from sets of matching characteristics, unless the characteristics measured are known to be absolutely unique in the population. This kind of uniqueness probably does not exist in the real world – as graphically demonstrated by <a href="http://www.thefingerprintinquiryscotland.org.uk/inquiry/21.html">recent fingerprint miss-attributions in Scotland</a> and <a href="http://www.justice.gov/oig/special/s0601/exec.pdf">in the US</a>.</p>
<p>So with DNA profiling as the new forensic science model, nobody should assert or believe that a matching fingerprint or other forensic trace means “it’s definitely him”. Yet the impression is that many forensic scientists have failed to grasp these radical implications, and continue to make claims for their evidence that lack foundation in either logic or science.</p>
<h2>In search of a remedy</h2>
<p>For an effective prescription for institutional reform there needs to be an intelligent diagnosis of the existing ailments. Simplistic solutions, or those predicated on superficial misunderstandings of criminal procedure, are liable to do more harm than good. Modest but effective reforms include greater pre-trial dialogue between legal teams, only putting disputed facts before a jury, reinforcing professional ethics among lawyers and expert witnesses, proper scrutiny of scientific evidence before admitting it, and educational initiatives such as the Royal Statistical Society’s <a href="http://www.rss.org.uk/RSS/Influencing_Change/Statistics_and_the_law/Practitioner_guides/RSS/Influencing_Change/Current_projects_sub/Statistics_and_the_law_sub/Practitioner_guides.aspx">guides for interpretation of statistics</a>.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/76672/original/image-20150331-1249-1ibxngh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/76672/original/image-20150331-1249-1ibxngh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/76672/original/image-20150331-1249-1ibxngh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=626&fit=crop&dpr=1 600w, https://images.theconversation.com/files/76672/original/image-20150331-1249-1ibxngh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=626&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/76672/original/image-20150331-1249-1ibxngh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=626&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/76672/original/image-20150331-1249-1ibxngh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=786&fit=crop&dpr=1 754w, https://images.theconversation.com/files/76672/original/image-20150331-1249-1ibxngh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=786&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/76672/original/image-20150331-1249-1ibxngh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=786&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="attribution"><span class="source">print by polygraphus/www.shutterstock</span></span>
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<p>Unfortunately, in a moment of penny-pinching madness that future governments may regard with incomprehension, the UK coalition government <a href="http://www.bbc.co.uk/news/uk-11989225">closed down the world-famous Forensic Science Service</a>, arguing – quite improbably – that the private sector would fill the gap. </p>
<p>There are now serious worries, <a href="http://www.parliament.uk/business/committees/committees-a-z/commons-select/science-and-technology-committee/news/130725-forensic-science-report-published/">expressed by a parlimentary select committee </a> and in a <a href="http://www.bbc.co.uk/news/science-environment-30909722">National Audit Commission report</a>, that this move to free-market forensics is not meeting the justice system’s need for high-quality scientific support and has put in jeopardy long-term forensic research, development and training. </p>
<p>The closure stands against a landscape of “austerity justice”, across which swingeing cuts to legal aid raises serious questions about the viability of effective criminal defence in England and Wales. Meanwhile, the <a href="https://www.gov.uk/government/organisations/forensic-science-regulator">Forensic Science Regulator</a>, professional bodies such as the <a href="http://www.forensic-science-society.org.uk/home">Chartered Society of Forensic Sciences</a> and other key stakeholders such as academic departments must do what they can to pick up the slack, in an effort to ensure that forensic evidence generated and presented in criminal proceedings remains fit for justice. </p>
<p>The price of failure will be paid not by politicians in Westminster, nor by prosecutors, nor by free-market forensic practitioners, but by the victims of miscarriages of justice and through damage to public confidence in the legal system. Something that, in an all-too-familiar historical pattern, may not become apparent for many years, or even decades, to come.</p><img src="https://counter.theconversation.com/content/39230/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paul Roberts was received a Nuffield Open Door grant as co-principal investigator (with Professor Colin Aitken, Edinburgh) to study probability and statistical evidence in the administration of criminal justice. He is a member of JUSTICE, and various professional and learned societies associated with law and criminal justice. The views expressed here are personal and not those of the Nuffield Council, JUSTICE or other bodies.</span></em></p>Forensic science has revolutionised justice, but we may have too much faith in it.Paul Roberts, Professor of Criminal Jurisprudence, University of NottinghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/379022015-03-16T19:15:14Z2015-03-16T19:15:14ZCyber CSI: the challenges of digital forensics<figure><img src="https://images.theconversation.com/files/74578/original/image-20150312-7144-18ltm1d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Forensics is a very different business when it comes to technology.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/isherwoodchris/6912080969/in/photolist-bwNdRP-2hfLti-6DawT3-2XnEG-66Ktk3-7VNV7v-fA6sq9-5hTyYZ-nHfNuH-8FmrvY-4JX9-pyHCWo-55pJxp-jUjG4j-oHRusq-bvo5TK-fuwdri-cJWXWf-81qMNV-qpZTxJ-jdypb2-nvpta9-6ySKyQ-2AUWum-nwqgYP-oZPqhm-cLeN4b-bD3stx-qGpj6n-qEhm8E-bouBAJ-ofLef7-rhaBGD-qq9yy2-tucY2-fuwd7D-fuw6PT-jFx4cM-qq1Haj-qq88aR-qq9yEz-bq1X3o-9tmFNJ-dYPPLV-hQj94X-5xwmbv-5LrvNQ-9JLHuJ-fuwa9n-51D189">Chris Isherwood/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Forensics is changing in the digital age, and the legal system is still catching up when it comes to properly employing digital evidence.</p>
<p>Broadly speaking, digital evidence is information found on a wide range of electronic devices that is useful in court because of its probative value. It’s like the digital equivalent of a fingerprint or a muddy boot. </p>
<p>However, digital evidence tendered in court often fails to meet the same high standards expected of more established forensics practices, particularly in ensuring the evidence is what it purports to be. </p>
<h2>Technology changes evidence</h2>
<p>This is not the first time that technology has impacted the way evidence is gathered and presented in courts. And it’s not the first time that there have been problems in the way new evidence is used.</p>
<p>You might remember the case of the death of <a href="http://adb.anu.edu.au/biography/chamberlain-azaria-chantel-9719">Azaria Chamberlain</a> at Ayers Rock (Uluru) more than 30 years ago. Forensics played a key role in the conviction of Lindy Chamberlain in 1982. However, her conviction was later reversed in 1988 following closer scrutiny of the evidence.</p>
<p>Subsequent <a href="https://theconversation.com/azaria-chamberlain-inquest-forget-the-dingo-jokes-and-recognise-lindys-trauma-7590">coronial inquests</a>, a court case featuring controversial DNA forensic evidence, and the subsequent <a href="http://www.nt.gov.au/justice/courtsupp/coroner/findings/other/chamberlain_3.pdf">Australian Royal Commission</a> into Azaria’s death, resulted in a fundamental reconsideration of Australian forensic practices.</p>
<p>There is still a vigorous debate in the legal world over the usage and reliability of <a href="https://theconversation.com/we-need-to-rethink-the-relationship-between-forensic-science-and-the-law-37141">DNA evidence</a>, for example. This is now being mirrored in more recent court challenges over the use of digital evidence. </p>
<p>The special properties and technical complexity of digital evidence often makes it even more challenging, as courts find it difficult to understand the true nature and value of that evidence.</p>
<p>In fact, my first role as a digital forensics consultant is typically to act as an interpreter, explaining what the evidence means in a legal context. </p>
<h2>Cyber evidence</h2>
<p>It is increasingly common for criminal trials to rely on digital evidence. And, regrettably, it is not uncommon for innocents to be convicted and guilty people acquitted because of digital evidence.</p>
<p>There are several reasons for this. Firstly, the evidence might be compelling at first glance, but it could be misleading. The defendant may also have limited financial resources to rebut the evidence. The defence lawyers might also misread the evidence. Plea-bargaining offers can also lessen sentences. </p>
<p>Conversely, other investigations may not get to trial because of the complexity or incompleteness of the evidence.</p>
<p>Worryingly, some defendants are pleading guilty based on what appears to be overwhelming hearsay digital evidence without robust defence rebuttal. In these cases, the defence lawyer – whose job it is to analyse the evidence – may simply not understand it. This is why external digital forensics consultants can be so important.</p>
<p>However, the high cost of mounting a defence using forensic practitioners is often beyond the financial reach of many. For those qualified to receive <a href="https://theconversation.com/au/topics/legal-aid">legal aid</a>, it is increasingly hard to obtain sufficient funding because of stringent budgeting regimes in various Australian jurisdictions. </p>
<p>Other factors can affect the validity of the evidence, including: failure of the prosecution or a plaintiff to report exculpatory data; evidence taken out of context and misinterpreted; failure to identify relevant evidence; system and application processing errors; and so forth. </p>
<p>Investigators undertaking these important but tedious tasks are often under-resourced, over-burdened with complex cases, increasingly large and complex datasets, etc. </p>
<p>Forensic analyses and evidence presentations are sometimes confounded by inexperienced investigators and communicators, which is further exacerbated by faulty case management.</p>
<p>Another problem issue is the paucity of reliable forensic tools and processes that meet the needs of investigators and the expectations of the courts. However, I also suspect some courts in Australia and elsewhere may be unaware of these undercurrents, or what standards they should expect of the evidence.</p>
<h2>Getting it right</h2>
<p>Digital forensics is still in its infancy, and it is more of an art form lacking broad scientific standards to supports its use as evidence. </p>
<p>There is a call among researchers to test and trial better forensic practices and forensic tools. This is especially important due to the increasing size of data storage on some personal computing devices, let alone cloud and network storage, which presents greater recovery and jurisdictional challenges to practitioners.</p>
<p>We also need new tools and processes capable of locating and recovering sufficient evidence from larger data sets quickly, efficiently and thoroughly. Forensic tools are often commercial products, thus profit-driven rather than science-based, and do not fulfil real forensic needs. They increasingly fail to identify all evidence from larger datasets in a timely manner. The processes used by law enforcement tend to be agency-centric with little consensus on practice, standards and processes and sharing of case knowledge.</p>
<p><a href="https://theconversation.com/au/topics/cyber-insecurity">Cyber security threats</a> to governments, businesses and individuals highlight our vulnerability to malicious attacks on our information assets and networks. Prevention and threat mitigation is topical, but we often overlook the simple act of bringing miscreants to justice and proving the innocence of those framed by their actions. </p>
<p>There is an old adage in forensics (thanks to Arthur Conan Doyle’s fictional detective <a href="http://www.goodreads.com/quotes/124175-there-is-nothing-more-deceptive-than-an-obvious-fact">Sherlock Holmes</a>): “There is nothing more deceptive than an obvious fact.” This also applies to digital forensics, where I have all too often encountered cases of investigator bias and a laziness when seeking the truth. </p>
<p>Encouragingly, sounder tools and processes are emerging that I expect will rejuvenate this emerging discipline.</p><img src="https://counter.theconversation.com/content/37902/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard Boddington works for Xtremeforensics (<a href="http://xtremeforensics.com/">http://xtremeforensics.com/</a>) and consults to TSW Analytical P/L (<a href="http://www.tswanalytical.com.au/home.html">http://www.tswanalytical.com.au/home.html</a>) .</span></em></p>Forensics is changing in the digital age, and the legal system is still catching up in terms of how it uses digital evidence.Richard Boddington, PhD student in computer science, Murdoch UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/371412015-02-20T12:16:49Z2015-02-20T12:16:49ZWe need to rethink the relationship between forensic science and the law<figure><img src="https://images.theconversation.com/files/72244/original/image-20150217-19493-1ufmt40.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Advances in science are causing problems in courtrooms</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?lang=en&language=en&ref_site=photo&search_source=search_form&version=llv1&anyorall=all&safesearch=1&use_local_boost=1&searchterm=forensic%20evidence&show_color_wheel=1&orient=&commercial_ok=&media_type=images&search_cat=&searchtermx=&photographer_name=&people_gender=&people_age=&people_ethnicity=&people_number=&color=&page=1&inline=227858284">Petretei</a></span></figcaption></figure><p>Despite what we see on television, forensic science is not always easy to understand or simple to convey to a jury, many of whom may not have studied science since they were in school. When a case fails in the courtroom, maybe because the scientist was inexperienced, or there were flaws in the science presented, it creates the potential for a miscarriage of justice – something to be avoided at all costs. </p>
<p>This was illustrated recently in a violent crime case in the US when a court refused to grant admissibility to a particular type of DNA <a href="http://www.nydailynews.com/new-york/nyc-crime/judge-tosses-types-dna-testing-article-1.2065795">evidence</a> because its interpretation had not yet been agreed within the scientific community and it was too complex for the jury to understand.</p>
<p>The judge told the court: </p>
<blockquote>
<p>To have a technique that is so controversial that the community of scientists who are experts in the field can’t agree on it and then to throw it in front of a lay jury and expect them to be able to make sense of it, is just the opposite of what the [rules on admissibility of evidence are] all about.</p>
</blockquote>
<p>Indeed, why should we expect lawyers or the public to understand science? The courtroom is a place where language can become severely challenging, where what is said may be at odds with what is heard. This is a particular issue for some types of evidence that rely, for example, on complex statistical analysis.</p>
<p>Both the scientist and the court have a duty to ensure that each party does their utmost to ensure that the jury understands the capabilities and limitations of any science presented to them. The scientists must be able to convey their often complex subject as simply as possible. Only then will the lawyers and judge be able to guide the jury to reach a secure and informed decision. </p>
<h2>The limits of scientific influence</h2>
<p>One core problem is that the scientist and the lawyer rarely meet before any courtroom confrontation. And the idea that a scientist might offer advice to a judge outside of the courtroom is almost uncharted territory in the UK. </p>
<p>Yet it is the trial judge who must decide whether there is sufficient robust underpinning in scientific evidence to let it be heard by the jury. They have to be sufficiently confident that the science establishes the fact in question and will withstand reasonable cross-examination that will assist the triers of fact.</p>
<p>Without training, how comfortable can the judge be to adopt this role – especially in complex cases such as those involving the interpretation of mixed-DNA profiles?</p>
<p>If the judiciary feel unable to do this, perhaps the scientist must assume the responsibility of teacher to convey the complexity of their science in a way that will be understood.</p>
<h2>A better way forward</h2>
<p>The reality is that the courtroom is the place where lawyers should be examining the case-specific science and not the basic underpinning value of the overarching scientific subject. The courtroom is not the classroom, so the time for teaching is during the preparatory stages before the business of testimony and evidence gets underway. </p>
<p>If all the scientific limitations could be agreed beforehand, this would leave only the details that relate to the case and the interpretation of the case-specific evidence to be addressed in the court. </p>
<p>The Lord Chief Justice of England and Wales last autumn <a href="http://www.judiciary.gov.uk/wp-content/uploads/2014/10/kalisher-lecture-expert-evidence-oct-14.pdf">called for</a> a set of judicial primers, pieces of “plain English” that will relay core scientific principles in a way that is understandable by lawyer, judge and jury. He reiterated this call <a href="https://royalsociety.org/events/2015/02/forensic-science/">recently</a> at a meeting hosted by the Royal Society in London that was agreed as a priority first step towards disrupting the communication logjam. </p>
<p>Another issue is our understanding of the scientific limitations. The US National Academy of Science <a href="https://www.ncjrs.gov/pdffiles1/nij/grants/228091.pdf">published a report</a> in 2009 that was a damning indictment of the lack of investment in forensic research and the shaky nature of basic scientific underpinning in most forensic sciences. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/72360/original/image-20150218-20802-cjy7qi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/72360/original/image-20150218-20802-cjy7qi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/72360/original/image-20150218-20802-cjy7qi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=340&fit=crop&dpr=1 600w, https://images.theconversation.com/files/72360/original/image-20150218-20802-cjy7qi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=340&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/72360/original/image-20150218-20802-cjy7qi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=340&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/72360/original/image-20150218-20802-cjy7qi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=427&fit=crop&dpr=1 754w, https://images.theconversation.com/files/72360/original/image-20150218-20802-cjy7qi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=427&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/72360/original/image-20150218-20802-cjy7qi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=427&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">National Academy of Science has bemoaned the state of forensic science.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/nationalacademyofsciences/14711963629/in/photolist-ghAQPo-hnZoba-5d1HxG-J2up8-oGgAkD-oq3Eek-7ofpYo-RmE8f-5jNXHp-bsZZVN-8bDQCz-dGPmjT-dGUJDq-dGUMv9-dGPjhk-dGPoGn-dGUJ2G-dGPmZK-dGPmLi-dGUPJw-jx4Pt-4gUgQy-dGPncB-dGPnH2-dGUN5E-dGPjEX-dGULWj-dGUHrC-dGUHKA-dGPpo6-dGPghi-dGUKZ1-dGULF7-dGUHem-dGPiBa-dGPoTg-dGUGrY-dGPnqD-dGPgwH-dGUJVf-dGPp8D-dGUPWN-dGUPxN-dGPj6R-dGUHCs-dGUJs1-dGPjSB-dGPkGv-dGPiTc-fbkrXV">NAS</a></span>
</figcaption>
</figure>
<p>In the past 30 years the lion’s share of funding has been consumed by advances in DNA, while other subjects have suffered, be they trace evidence (such as hairs and fibres), ballistics, blood patterns or fires and explosions. This has meant that core research gaps in our knowledge remain. </p>
<p>A global strategic approach aiming to improve basic scientific underpinning must also lie at the core of any future advance to provide better science to the courts. This is vital for the health of the subject and in turn can only benefit justice in the long term. </p>
<p>In short, scientists must come together in partnership with the law and funders to ensure a product that is fit for purpose. This requires greater co-ordination and understanding between two ancient academic disciplines who have rarely been easy bedfellows: law and science. </p>
<p>Lifetimes of misunderstanding have built up around their gladiatorial arena and they no longer seem to speak a common language. It is time for a paradigm shift in their relationship, geared towards addressing areas of common and competing ground, talking about science in plain English and agreeing where the current research gaps exist and how we are best placed to fill them.</p><img src="https://counter.theconversation.com/content/37141/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Niamh Nic Daeid does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations. </span></em></p><p class="fine-print"><em><span>Sue Black does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Despite what we see on television, forensic science is not always easy to understand or simple to convey to a jury, many of whom may not have studied science since they were in school. When a case fails…Sue Black, Professor of Anatomy and Forensic Anthropology, University of DundeeNiamh Nic Daeid, Professor of Forensic Science and Director of Research at CAHID, University of DundeeLicensed as Creative Commons – attribution, no derivatives.