Abstract
From an early age, children are willing to pay a personal cost to punish others for violations that do not affect them directly. Various motivations underlie such "costly punishment": People may punish to enforce cooperative norms (amplifying punishment of in-groups) or to express anger at perpetrators (amplifying punishment of out-groups). Thus, group-related values and attitudes (e.g., how much one values fairness or feels out-group hostility) likely shape the development of group-related punishment. The present experiments (N = 269, ages 3-8 from across the United States) tested whether children's punishment varies according to their parents' political ideology-a possible proxy for the value systems transmitted to children intergenerationally. As hypothesized, parents' self-reported political ideology predicted variation in the punishment behavior of their children. Specifically, parental conservatism was associated with children's punishment of out-group members, and parental liberalism was associated with children's punishment of in-group members. These findings demonstrate how differences in group-related ideologies shape punishment across generations.