The Intergroup Foundations of Policy Influence

Abstract

Most decisions about policy adoption require preference aggregation, which makes it difficult to determine how and when an individual can influence policy change. Examining how frequently a judge is cited offers insight into this question. Drawing upon the psychological concept of social identity, we suggest that shared group memberships can account for differences in policy influence. We investigate this possibility using the demographic and professional group memberships of federal circuit court judges and an original dataset of citations among all published search and seizure cases from federal circuit courts from 1990 to 2010. The results indicate that shared professional characteristics do tend to lead to ingroup favoritism in citation decisions while only partial evidence of such a pattern emerges for demographic group memberships. There is evidence of ingroup favoritism among female and minority judges but none for male or white judges. Overall, judges appear to generally have greater influence on judges with shared characteristics. The findings have vital implications for our understanding of the diversification of policy-making institutions.