Deemed consent organ donation means that everyone is assumed to be an organ donor unless they opt out, but assuming consent raises some ethical issues.
The number of people choosing to become posthumous donors in the UK has reached 25.3m but this is still considerably lower than other countries.
A parliamentary committee report recommends the Australian government investigate whether an opt-out system could help increase donation rates. But the evidence suggests it wouldn't.
The family veto is morally repugnant unless removing it would result in a decrease in the supply of transplantable organs.