This case concerned the meaning of “honest but mistaken belief” in consent in sexual assault law. 

LEAF intervened before the Supreme Court of Canada. 


Warrant Officer J.G.A. Gagnon, a senior military official, was accused of sexually assaulting a colleague. Warrant Officer Gagnon argued that he believed the complainant was consenting because she was silent, opened her mouth (as if to receive a kiss), and moved her hips slightly. The complainant testified that she was not asked whether she wanted to engage in any sexual activity, and after she told the accused she did not want to proceed, he digitally penetrated her and attempted intercourse.  

The Chief Military Judge allowed the court martial panel to consider whether, even if the complainant had not consented, Warrant Officer Gagnon had honestly but mistakenly believed she had consented. The court martial panel acquitted Warrant Officer Gagnon. The Court Martial Appeal Court of Canada allowed the Crown’s appeal and ordered a new trial. Warrant Officer Gagnon appealed to the Supreme Court of Canada. 


LEAF argued that, for the defence of “honest but mistaken belief” in consent to apply, there needs to be an “air of reality” to all requirements of the defence – including that the accused took reasonable steps to make sure the complainant was consenting. To satisfy the “reasonable steps” requirement, the accused needs to have taken active, positive steps to confirm consent. And he cannot rely on the surrounding circumstances, ambiguous conduct or passivity by the complainant, or consent to a prior or different sexual act. In addition, where there is a power imbalance between the accused and the complainant, more substantial steps are required.  


In a brief judgment, the Supreme Court dismissed the appeal. The Court observed that there was no evidence that Warrant Officer Gagnon had taken reasonable steps to determine that the complainant was consenting. As a result, the defence of honest but mistaken belief should not have been left with the jury. 

LEAF is grateful to Kelly McMillan, Nasha Nijhawan, and Shaun O’Brien, counsel in this case, as well as Nadia Effendi, 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].