The respondent attacked his parents-in-law while sleepwalking, killing his mother-in-law and seriously injuring his father-in-law.
At trial, he presented a defence of non-insane automatism, supported by uncontradicted expert medical evidence that sleepwalking is a sleep disorder, not a neurological or psychiatric illness.
The trial judge left only the defence of non-insane automatism with the jury, which acquitted the respondent.
The Court of Appeal upheld the acquittal.
The Supreme Court of Canada dismissed the Crown's appeal, holding that on the evidence and policy considerations, sleepwalking in this case did not stem from a 'disease of the mind' and was properly classified as non-insane automatism, entitling the accused to an absolute acquittal.
