This case concerned the validity of the defence of honest but mistaken belief in consent in sexual assault trials. 

LEAF intervened before the Supreme Court of Canada 


Percival Whitley, Timothy Mowers, and a third man were convicted of the gang sexual assault of a woman. They argued that they mistakenly believed that the woman had consented because she did not object or offer physical resistance. The Ontario Court of Appeal dismissed their appeals. They then appealed to the Supreme Court of Canada. 


LEAF argued that the defence of mistaken belief in consent could not be used where the accused had made a mistake about the legal requirements of consent – for example, where the accused believed that a failure to say no meant the complainant had consented.  


The Supreme Court did not directly address whether the defence of mistaken belief in consent should have been available in this case. Instead, the Court said that, even if the defence should have been put to the jury, their verdict showed that they would have rejected the argument. As a result, the Court dismissed the appeal. 

LEAF is grateful to Chantal Tie, Diane Oleskiw, and Laurie Joe, counsel in this case, as well as Catharine Aitken, Ottawa agent for LEAF. 

Download the factum here.

Read the Supreme Court of Canada’s decision here

Our records are imperfect, but we are doing our best to update them – if you were involved with LEAF on this case but your name is not reflected here, please email us at [email protected].