Effect of Alcohol Intoxication on Bystander Intervention in a Vignette Depiction of Sexual Assault

Objective: Alcohol-related sexual violence remains a public health problem. Despite the popularity of sexual assault bystander intervention programs, these may be limited in addressing bystander intoxication because the effects of intoxication on intervening in a sexual assault are unknown. Therefore, we tested the effects of alcohol intoxication on the five steps of bystander intervention in a sexual assault vignette. Method: Young adults (N = 128; 50% women) were randomly assigned to consume alcohol (target blood alcohol concentration 0.08%; n = 64) or a nonalcoholic control beverage (n = 64) in a bar-laboratory. Next, participants were presented with a vignette describing events occurring in a convivial drinking context that ends with nonconsensual sexual behavior. Latane and Darley's bystander intervention model steps were assessed in a semistructured interview. Results: Participants in the control condition recalled the story more accurately (Step 1: notice the event) and reported greater risk/need for intervention (Step 2), but they did not differ on the latter three steps of bystander intervention compared with alcohol-condition participants. Intoxication effects were similar for men and women. Furthermore, risk/need for intervention (Step 2) partially mediated the effect of alcohol condition on personal responsibility (Step 3) and relative benefits versus costs from intervening (Step 4). Conclusions: Prevention programs should consider the effects of alcohol on detecting a sexual assault and the need to intervene. If intoxicated bystanders do not detect a sexual assault, then bystanders will not reach the crucial steps (i.e., taking responsibility for intervening; willingness and ability to intervene) required to intervene successfully.