The appellant was convicted of aggravated assault.
The Crown failed to disclose a statement made by an eyewitness, though a summary was included in police reports provided to the defence.
The Court of Appeal found that defence counsel had exercised due diligence in pursuing disclosure.
The Supreme Court of Canada held that the undisclosed statement could have affected the defence's strategy, such as the decision not to call evidence.
The Court concluded that the non-disclosure affected the fairness of the trial process and impaired the appellant's right to make full answer and defence.
The appeal was allowed and a new trial ordered.