The appellant shot and killed his grandfather and subsequently raised the defence of mental disorder at trial.
Two psychiatrists testified that the appellant suffered from paranoid schizophrenia and lacked the capacity to appreciate that his actions were morally wrong.
The Crown did not call rebuttal expert evidence but challenged the experts on cross-examination.
The jury convicted the appellant of second degree murder, and the Court of Appeal upheld the conviction.
The Supreme Court of Canada allowed the appeal, finding that the jury's verdict was unreasonable as the totality of the evidence, including the uncontradicted expert testimony, established that the appellant did not know his actions were morally wrong.
