The effects of group memberships of disaster victims and perpetrators on charitable donations were measured. In Study 1 (N = 92), victim group membership was experimentally varied to demonstrate an ingroup bias. In Study 2 (N = 84), a similar bias was demonstrated by varying perpetrator group membership. In Study 3 (N = 182), both victim and perpetrator group memberships were assessed. Perpetrator group membership interacted with victim group membership. Moreover, donations were highest when both victims and perpetrators shared a group membership. These effects were mediated by empathy with the victims, and perceived responsibility of the donor to intervene and aid the victim. Findings show that a salient perpetrator group can be harnessed to encourage helping of disaster victims.