Statement of purpose In approximately half of sexual assaults, the victim was under the influence of alcohol. The purpose of this study was to examine similarities and differences between perpetrators whose victims were drinking alcohol as compared to those whose victims were sober.

Methods/Approach 556 men completed an online survey. Discriminant function analysis was conducted to distinguish between perpetrators with victims who had consumed alcohol (n=87) and perpetrators with sober victims (n=109). Some participants later completed a laboratory dating simulation in which they went on virtual reality dates. Univariate analyses of variance were conducted to compare perpetrators with intoxicated victims (n=19) and sober victims (n=26).

Results Discriminant function analysis indicated that both groups of perpetrators had similar scores on personality traits including narcissism, and empathy. However, they differed on many attitudinal and behavioural characteristics. Men who assaulted women who had consumed alcohol reported higher levels of sexual dominance, positive attitudes about casual sex, rape myth acceptance, alcohol consumption, sex-related alcohol expectancies, and peer approval of getting drunk and forced sex. Further, they engaged in more sexual activity in the laboratory dating simulation, and gave themselves and the female agent more alcoholic drinks.

Conclusions These findings illuminate important differences between men who assault intoxicated women as compared to men who assault sober women. Perpetrators who sexually assault women under the influence of alcohol have a constellation of beliefs and behaviour associated with women and alcohol that increase their risk of perpetration.

Significance of Contributions to Injury and Violence Prevention Science Prevention programs need to consider the wide range of risk factors associated with sexual assault perpetration. Men who drink heavily and have strong sex-related alcohol expectancies need tailored programs to address these additional risk factors.