SCC Rules on Intellectual Disabilities and Equality.

• Author: McKay-Panos, Linda
• Position: HUMAN RIGHTS / SCC Rules on Intellectual Disabilities and Equality

A recent Supreme Court of Canada (SCC) case, R v Slatter, 2020 SCC 36, provided a strong statement about the treatment of evidence provided by witnesses who have intellectual or developmental disabilities.

Thomas Slatter was convicted at trial of sexually assaulting an intellectually disabled 21-year-old woman (J.M.). The defense appealed the decision to the Ontario Court of Appeal (ONCA). They argued, among other issues, that the trial judge erred by: "not properly assessing the reliability of J.M.'s evidence and failing to address the expert evidence of her suggestibility" (para 56).

At the OCNA, the defence counsel argued that, "while the trial judge thoroughly examined J.M.'s credibility, he failed to address his mind to the reliability of her evidence, especially her propensity for suggestibility" (para 57). The defence asserted that the trial judge's reasons were therefore insufficient (para 57).

At trial, the Crown introduced evidence from expert Dr. Jones to prove elements of the two offences for which Mr. Slatter had been charged. However, defence counsel thoroughly cross-examined Dr. Jones on J.M.'s suggestibility (para 61). Further, in his closing submissions, defence counsel repeatedly stressed the importance of this aspect of Dr. Jones' evidence (para 62).

The majority of the ONCA stated (at para 70):

As the Crown correctly submits, a trial judge's findings on the credibility and reliability are entitled to deference... The problem in this case is that there is nothing upon which to defer on the issue of suggestibility. The trial judge made no finding. He may have found this evidence to be inconsequential. He may have inadvertently overlooked this aspect of Dr. Jones' evidence. It is a matter of speculation. The Crown essentially asks this court to review the record and, even in light of Dr. Jones' evidence, find that J.M.'s reliability was not compromised by her suggestibility during the early stages of the investigation. This was a matter for the trial judge. It is beyond the scope of proper appellate review.

The ONCA majority allowed the appeal and ordered a new trial.

Madam Justice Pepall (ONCA) dissented. She noted that, in particular, the appellant relied on the testimony of Dr. Jones that people with intellectual disabilities are more likely to be suggestible, especially when the questioner is in a position of authority or trust.

Justice Pepall continued (at para 121):

Dr. Jones' evidence was that the complainant was...