Pauline Bouchard

The accused was charged with sexual assaults on two young male children.

At trial, he sought to introduce expert psychiatric evidence, including penile plethysmograph test results, to show he lacked the distinctive personality traits of someone who would commit such offences.

The trial judge excluded the evidence, finding it did not meet the Mohan criteria for admissibility, and convicted the accused.

The Court of Appeal allowed the appeal and ordered a new trial.

The Supreme Court of Canada allowed the Crown's appeal and restored the conviction, holding that the trial judge properly exercised his gatekeeper function in excluding the novel scientific evidence due to its lack of reliability and failure to establish a standard profile for the distinctive group of offenders.

The accused pleaded guilty to 15 counts arising from a home invasion robbery and was sentenced to 10.5 years imprisonment.

On appeal, the accused sought to introduce fresh evidence in the form of two expert psychological/psychiatric reports.

The Court of Appeal admitted the reports and reduced the sentence.

The Supreme Court of Canada allowed the Crown's appeal, holding that the Palmer criteria for admitting fresh evidence apply equally to appeals against sentence as they do to appeals against conviction.

The Court found the expert reports inadmissible because they were based on a version of facts rejected by the trial judge, thus lacking sufficient probative value to affect the result.

However, the Court substituted a sentence of 8.5 years due to an error in principle by the trial judge.