LAST week, a provincial court judge declared a delusional 56-year-old man who stabbed his neighbour with a knife not criminally responsible for the assault. Coincidentally, a few days later, Carole de Delley, mother of Tim McLean, who was beheaded by Vince Li on a Greyhound bus in 2008, announced she was ending her petition to change the legal consequences of a finding of not criminally responsible. She had long promoted "Tim's Law," which would have resulted in any mentally disordered killer being automatically confined to a treatment facility for life.
Both actions spawned criticism of NCR law, much of it ill-informed.
A basic principle of Canada's criminal law is that the Crown must prove not only that an accused committed a criminal act, but also had a "guilty mind" when doing so. In other words, he has to have acted willfully. If he didn't appreciate the nature of the act, or that it was wrong, he can't be convicted.
The criminal law's so-called insanity defence taps into this fundamental principle. The defence also has a solid ethical underpinning: It's morally wrong for the state to punish someone who couldn't grasp that what he did constituted a crime. That's why we don't intentionally imprison mentally ill people.
Oddly, it's also linked to why we no longer try animals in court. For hundreds of years, non-humans -- mainly pigs, cattle, goats and horses -- were tried in our common-law and ecclesiastical courts, mostly for capital crimes against humans. Not until the 18th century did the courts determine animals lack the moral agency to be culpable of murder.
The criminal law's treatment of mentally disordered offenders has evolved over the centuries, mirroring advances in clinical psychology, psychiatry and mental-health treatment generally.
Mentally ill people charged with a crime deserve a progressive legal regime. Campaigns to lock up such offenders who commit murder amount to an attempt to return the law to a state of ignorance rightly abandoned.