The present study examined bystanders' justice perceptions about co‐punishment events. In a sample of 169 logistic officers in the Taiwanese military, responsibility attributions (i.e. liability attributed to co‐punished persons) had a negative relationship with perceived harshness, and a positive relationship with perceived procedural justice. In addition, the effects of responsibility attributions on procedural justice were weaker if the person perceived stronger rather than weaker organizational norms of co‐punishment.