Conclusion

• Author: Kent Roach
• Profession: Faculty of Law and Centre of Criminology. University of Toronto
• Pages: 314-316

Page 314

The classification of diseases of the mind has been the most dynamic and uncertain feature of the law defining the defences of mental disorder and automatism. In Parks,¹³⁵the Supreme Court held that sleepwalking was not a disease of the mind and indicated that the proper verdict, if the jury found that the accused had acted in an involuntary state, was an acquittal. This remains the law today with the important exception that the accused would now have the burden of establishing his defence of non-mental disorder automatism on a balance of probabilities. In Stone,¹³⁶the Supreme Court not only imposed a burden on the accused of establishing an automatism defence on a balance of probabilities, but also followed Rabey¹³⁷by indicating that only extraordinary emotional blows that would cause an average person to go into a disassociative state would produce a defence of non-mental disorder automatism and its consequent verdict of acquittal. In all but the most extraordinary cases, an emotional blow producing an automatic state will result in a verdict of not criminally responsible by reason of mental disorder, even if the accused was not diagnosed by a psychiatrist with a mental disorder. In contrast to its earlier decision in Parks,

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the Court in Stone has significantly restricted the defence of non-insane automatism. In doing so, the Court has made it much less likely that the jury will ever get to consider such a defence even in cases such as Parks where the accused commits a crime while sleepwalking. This is unfortunate because there was no evidence that the defence was being abused in the period between Parks and Stone.

The only virtue of Stone is its recognition of a holistic and policy-driven approach to defining a disease of the mind. In this, the Court has been consistent with Parks and wisely avoided the absurd results that English courts, given their exclusive reliance on internal cause theories, have produced in cases holding that sleepwalkers, epileptics, and diabetics who act while in an automatic state should be forced into the insanity defence. Canadian courts will only use the presence of internal causes as a factor in determining disease of the mind. They may, as in Parks, depart from reliance on that factor if it does not accord with the overall policy objectives of using the mental disorder defence to protect the public.

The exact contours of the two alternative arms of the section 16 defence are...