Money in Judicial Politics: Individual Contributions and Collective Decisions∗

We study how campaign contributions affect the voting strategies and effectiveness of justices in the Supreme Court of eight US states. A judge’s voting strategy leans more heavily towards an interest group the larger are its contributions to the judge, and the smaller are its contributions to other members of the court. This panel effect is consistent with an equilibrium response to contributions to other members of the court. Observed contributions have a large effect on the decisions and effectiveness of individual judges, but tend to counterbalance each other, producing a small effect on the decisions and effectiveness of the Court. ∗We thank Juliana Bambaci, Sanford Gordon, Francesco Trebbi, and participants at seminars at UCSD, Princeton, Yale, and the Political Institutions and Economic Policy, MPSA and AEA conferences, for useful comments. Financial support from NSF Grants SES-1061326 (Iaryczower) and SES-1061266 (Shum) is gratefully acknowledged. †Department of Politics, Princeton University, Princeton NJ 08540, and Division of Humanities and Social Sciences, California Institute of Technology, Pasadena, California 91125, USA, emails: [email protected], [email protected].