On May 15, 1800 James Hadfield fired a pistol at King George III at the Theatre Royal in London, England. He missed his target and then addressed the King, “God bless your royal highness; I like you very well; you are a good fellow.” He was tried for high treason and defended by Thomas Erskine a prominent lawyer who convinced the judge that Hadfield only pretended to kill the King because he wanted to die and knew he would be killed for the attempt. Hadfield was found insane and ordered that he spend the rest of his life in a psychiatric hospital.

This case led to the passing of the Criminal Lunatics Act in 1800 which allowed insane defendants to be detained instead of being released back to their families for safe-keeping.

In January 1943, Daniel M’Naghten, a Scottish woodturner assassinated English civil servant Edward Drummond while suffering paranoid delusions. It’s generally thought that he was under the impression that he had shot the prime minister, Robert Peel. Drummond walked away from the shooting but died of complications five days later. M’Naghten was acquitted and sent to the Broadmoor Asylum which provoked an outcry in the press.

This led to the establishment of the M’Naughten rules, “To establish a defence on the ground of insanity it must be clearly proved, that, at the time of committing the act, the party accused was labouring under such a defect of reason from disease of the mind, as not to know the nature and quality of the act he was doing, or if he did know it, that he did not know that what he was doing was wrong.” which were used throughout the British Commonwealth for over 100 years. The rules represented a step backwards to the traditional test of criminal insanity and had they applied in M’Naghten’s own case, the verdict might have been different.

In 1892 Canada’s Criminal Code was enacted and drafted in a large part from British law including it’s laws on insanity and crime – including the N’Naghten rule. The same section incorporated a legal presumption of sanity, however, and an acquittal on account of insanity resulted in detention with all decisions regarding release to be decided by the Lieutenant Governor.

These laws were used until the Supreme Court of Canada ruled the insanity defence unconstitutional.

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