Revisiting the Defence of Diminished Responsibility

My goal in this article is to revisit the defence of diminished responsibility. There are three things that, taken together, suggest to me that a defence of diminished responsibility ought to be made available to certain individuals accused of certain criminal offences. The first is that Canadian criminal law already recognizes a number of defences that reflect ideas about diminished responsibility. The second is that despite the availability of these specific defences to criminal liability, no general defence of diminished responsibility is formally recognized in Canadian criminal law. And the third is that given the Supreme Court of Canada’s ongoing interest in the connection between criminal liability, fundamental justice, and the principle of normative involuntariness, we should take seriously the idea that a defence of diminished responsibility ought to be recognized and made available to certain offenders who suffer from substantial volitional impairments. My paradigmatic example of a volitional impairment is Fetal Alcohol Spectrum Disorder (FASD).