Social norm enforcement in ethnically diverse communities.

Recent waves of immigration to Western nations have fueled a debate over the consequences of ethnic diversity for social cohesion. One prominent argument in this debate holds that diversity is detrimental to trust and cooperation because individuals in heterogeneous communities face difficulties in enforcing social norms across ethnic lines. We examine this proposition in a field experiment involving real-life interactions among residents of multiethnic German neighborhoods. We find significant ethnic asymmetries in the pattern of norm enforcement: Members of the majority "native" German population are more active in sanctioning norm violations, while ethnic minorities are more likely to find themselves the target of sanctions. We interpret these results in light of prevailing status inequalities between ethnic minorities and the native majority. We further calculate that, as a result of ethnic discrimination, social control is likely to rise in communities with moderate minority population shares.