Internal and external sexual consent during events that involved alcohol, cannabis, or both

Background: Substance-involved sexual activity is common. Even though people recognize that substance-related impairment can be a barrier to people’s ability to consent to sexual activity, most do not believe that substance use automatically negates sexual consent. We extended previous work on substance-related effects on internal and external consent by investigating sexual events that involved alcohol, cannabis, or both. Method: For 28 days, 113 participants (MAge = 29.2 years, 57.5% women, 70.8% White) responded to three surveys per day on their personal devices. At time points when participants reported having engaged in partnered sexual activity, they were asked to report their alcohol use, cannabis use, internal consent feelings, and external consent communication. Results: Across 1189 partnered sexual events, 31.5% involved alcohol, cannabis, or both. Sexual events that involved combined use were associated with diminished feelings of safety/comfort and feelings that the sexual act was consensual, compared with events that involved neither substance. Greater levels of alcohol consumptions were descriptively associated with lower ratings of internal sexual consent. Conclusions: We found that combined use of alcohol and cannabis may lead to lower internal sexual consent than using one or no substances—potentially due to greater levels of impairment associated with polysubstance use. Sexual health education programs should consider more nuanced approaches to teaching people how to navigate substance use and sexual consent