Researchers at Dalhousie University have published a paper warning that smoking cannabis within three hours of driving doubles the chance of collision.
The authors claim this is the first observational study of the effects of cannabis on drivers and its link to collisions. Previous research had combined the results of alcohol and other drugs with cannabis, resulting in a lack of concurrent opinion.
The paper suggests that the information gathered can be used in campaigns against driving while under the effects of drugs.
Read more at BMJ