Her Majesty the Queen v. Thomas Slatter

(Ontario) (Criminal) (As of Right)

(Publication ban in case)


Criminal law - Appeals - Sufficiency of reasons - Whether the majority of the Court of Appeal erred in law in finding that the trial judge’s reasons were insufficient because he: failed to address the complainant’s reliability; found that the complainant’s evidence was self-corroborating; and failed to provide reasons for rejecting the defence evidence.


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At trial, the respondent, Mr. Slatter, was convicted of sexual assault but found not guilty of sexual exploitation of a person with a disability. A majority of the Ontario Court of Appeal allowed Mr. Slatter’s appeal against the conviction and ordered a new trial on the count of sexual assault. In its view, the trial judge’s reasons were insufficient. In dissent, Pepall J.A. would have dismissed the appeal as, in her view, Mr. Slatter had a fair trial. The failure of the trial judge to expressly address in his reasons the defence submission that the complainant was suggestible did not render the trial judge’s reasons for decision insufficient thus requiring a new trial. In addition, Pepall J.A. disagreed that the trial judge erred in failing to explain his rejection of the defence evidence. Finally, standing alone, the fact that the trial judge improperly relied on the complainant’s evidence as being self-corroborating was not enough to allow the appeal.

Lower Court Rulings

December 18, 2017
Ontario Superior Court of Justice

Respondent convicted of sexual assault and found not guilty of sexual exploitation of a person with a disability.
October 8, 2019
Court of Appeal for Ontario

2019 ONCA 807, C65248
Appeal allowed and new trial ordered on count of sexual assault.