Objectives: Bystander studies have rarely considered the victimization risk associated with intervention into violent, dangerous emergencies. To address this gap, we aim to identify factors that influence bystanders' risk of being physically victimized. Methods:We observed bystander behavior from video surveillance footage of naturally occurring violence in night-time economy settings, and data was analyzed with a logistic regression model. Results: Data shows that approximately one out of six interventions results in some type of victimization, typically with a relatively low degree of severity. The bystander's social group membership, the setting of the emergency, and the bystander's intervention type are estimated as risk factors for victimization. Conclusions: Previous research suggests that a bystander's social group membership with victims promotes intervention behavior. Our results expand the role of social group membership as being a factor that also influences whether the intervening bystander is victimized.

Are individuals willing to intervene in public violence? Half a century of research on the “bystander effect” suggests that the more bystanders present at an emergency, the less likely each of them is to provide help. However, recent meta‐analytical evidence questions whether this effect generalizes to violent emergencies. Besides the number of bystanders present, an alternative line of research suggests that pre‐existing social relations between bystanders and conflict participants are important for explaining whether bystanders provide help. The current paper offers a rare comparison of both factors—social relations and the number of bystanders present—as predictors of bystander intervention in real‐life violent emergencies. We systematically observed the behavior of 764 bystanders across 81 violent incidents recorded by surveillance cameras in Copenhagen, Denmark. Bystanders were sampled with a case–control design, their behavior was observed and coded, and the probability of intervention was estimated with multilevel regression analyses. The results confirm our predicted association between social relations and intervention. However, rather than the expected reversed bystander effect, we found a classical bystander effect, as bystanders were less likely to intervene with increasing bystander presence. The effect of social relations on intervention was larger in magnitude than the effect of the number of bystanders. We assess these findings in light of recent discussions about the influence of group size and social relations in human helping. Further, we discuss the utility of video data for the assessment of real‐life bystander behavior.

Objectives: Bystander studies have rarely considered the victimization risk associated with intervention into violent, dangerous emergencies. To address this gap, we aim to identify factors that influence bystanders' risk of being physically victimized. Method: We observed bystander behavior from video surveillance footage of naturally occurring violence in nighttime economy settings, and data were analyzed with a logistic regression model. Results: Data show that approximately one of the six interventions results in some type of victimization, typically with a relatively low degree of severity.

Face masks have been widely employed as a personal protective measure during the COVID-19 pandemic. However, concerns remain that masks create a false sense of security that reduces adherence to other public health measures, including social distancing. This paper tested whether mask-wearing was negatively associated with social distancing compliance. In two studies, we combined video-observational records of public mask-wearing in two Dutch cities with a natural-experimental approach to evaluate the effect of an area-based mask mandate. We found no observational evidence of an association between mask-wearing and social distancing but found a positive link between crowding and social distancing violations. Our natural-experimental analysis showed that an area-based mask mandate did not significantly affect social distancing or crowding levels. Our results alleviate the concern that mask use reduces social distancing compliance or increases crowding levels. On the other hand, crowding reduction may be a viable strategy to mitigate social distancing violations.