The accused was charged with sexual assault causing bodily harm.
At trial, the Crown introduced similar fact evidence from the accused's former wife regarding alleged past assaults to show a propensity for non-consensual, painful sex.
The accused argued the evidence was highly prejudicial and that the former wife and the complainant had colluded.
The trial judge admitted the evidence and left the issue of collusion to the jury, resulting in a conviction.
The Court of Appeal ordered a new trial.
The Supreme Court of Canada dismissed the Crown's appeal, holding that the similar fact evidence was wrongly admitted because its prejudicial effect outweighed its probative value, and the trial judge erred in law by failing to resolve the issue of collusion as a condition precedent to admissibility.