In Canadian criminal law, consent to sexual activity is defined in section 273.1 of the Criminal Code as the voluntary agreement of the complainant to engage in the sexual activity in question. Consent must be present at the time the sexual activity takes place — a prior agreement or general willingness is not sufficient.
The Criminal Code specifies circumstances where consent is not obtained: where the agreement is expressed by someone other than the complainant, where the complainant is incapable of consenting (including due to intoxication or unconsciousness), where the accused induces consent by abusing a position of trust, power, or authority, where the complainant expresses a lack of agreement, or where the complainant, having consented, expresses a lack of agreement to continue. Consent obtained through fraud about the nature of the act or the identity of the accused is also not valid.
The accused's honest but mistaken belief in consent is a defence under section 273.2, but only if the accused took reasonable steps to ascertain consent. The accused cannot rely on self-induced intoxication, recklessness, or wilful blindness to support this defence. Consent is the central issue in most sexual assault trials, and the legal framework is highly technical.