canada
The voluntariness of the intoxication is a red herring. It plays zero role in the analysis of sexual assault. What matters is:
- whether there was sexual touching;
- whether the complainant had the capacity to consent;
- whether the complainant in fact consented;
- whether the accused took reasonable steps to ascertain consent; and
- whether the accused had an honest belief that the complainant had communicated consent.
The elements of sexual assault
To prove an offence, the Crown (prosecution) must establish both the actus reus and mens rea of the offence.
The actus reus of sexual assault is that:
- there is sexual touching;
- there is no consent to that specific sexual touching in the mind of the complainant.
"Complainant" simply means the "victim of the alleged offence" (Criminal Code, s. 2).
Criminal Code, s. 273.1:
Subject to subsection (2) and subsection 265(3), consent means, for the purposes of sections 271, 272 and 273, the voluntary agreement of the complainant to engage in the sexual activity in question.
Consent for the purpose of sexual assault is only the subjective consent by the complainant. "For the purposes of the actus reus 'consent' means that the complainant in her mind wanted the sexual touching to take place" (R. v. Ewanchuk, [1999] 1 SCR 330).
"The mens rea is the intention to touch, knowing of, or being reckless of or wilfully blind to, a lack of consent, either by words or actions, from the person being touched" (R. v. Ewanchuk, [1999] 1 S.C.R. 330).
Intoxication of the complainant — effect on capacity to consent
It is not the case that any degree of intoxication precludes consent. See R. v. G.F., 2021 SCC 20, para. 84. However, intoxication can reach the level that removes a person's capacity to consent. Capacity to consent is a precondition to consent: no capacity; no consent. Capacity is a question of fact and requires that the person "have an operating mind capable of understanding each element of the sexual activity in question" (R. v. G.F., 2021 SCC 20, para. 55). To have the capacity to consent, the complainant must be capable of understanding four things (para. 57):
the physical act;
that the act is sexual in nature;
the specific identity of the complainant’s partner or partners; and
that they have the choice to refuse to participate in the sexual activity.
It is not true that "a women who is intoxicated cannot give her legal consent for sex" (see R. v. G.F., 2021 SCC 20, para. 84: "equating any degree of intoxication with incapacity would be wrong in law").
Example of having a reasonable doubt as to non-capacity
See R. v. Le Goff, 2022 ONSC 609 for an example where the Crown failed to prove that the complainant lacked the capacity to consent. The judge accepted that the complainant was intoxicated and that she had nearly no memory of what happened. The judge noted evidence that the complainant had appeared "intoxicated but functional... she did not lose motor control, slur her speech, or pass out." The judge noted evidence that later in the evening, the complainant was asleep on a bed, and that her friends were unable to get her up. One witness thought the complainant was "too drunk to be roused." However, even with this evidence, the judge was left with a reasonable doubt as to whether the complainant lacked the capacity to consent to sexual activity. There was the reasonable possibility that she continued to have an operating mind despite her intoxication and lack of memory."
Defence of "honest but mistaken belief in communicated consent"
Even if a judge finds that a complainant lacked the capacity to consent, there may be a defence available to the accused if they held an honest but mistaken belief that the complainant communicated consent. In order for this defence to be available, however, the accused must have taken reasonable steps to ascertain whether the complainant was consenting. Another Q&A answers what can and cannot constitute reasonable steps. In the context of an intoxicated complainant, the threshold for satisfying the reasonable steps requirement will be elevated, especially where the complainant may not even have the capacity to consent.
"Is it at all common...?"
The question of capacity in the context of an intoxicated complainant is a frequent issue in sexual assault charges. See this search in a database of reported decisions from Canada. This does not even include those many unreported decisions from provincial courts, guilty pleas, and other dispositions of charges that don't result in published reasons.
Prosecutorial discretion
We cannot know how prosecutors would deal with any given complaint. Charging decisions are discretionary. The guidelines depend on the province. But generally, to bring a charge, Crown counsel must believe there is a substantial likelihood of conviction (in B.C.) (or reasonable prospect of conviction in Ontario) and that the public interest requires a prosecution.