Supreme Court Appointments as a Move-the-Median Game


  • Communications with Silvia Console-Battilana, Chuck Cameron, Alex Hirsch, Ken Shepsle. Chuck Shipan, and Alan Wiseman are gratefully acknowledged.

Keith Krehbiel is Edward B. Rust professor of political science, Stanford Graduate School of Business, 518 Memorial Way, Stanford University, Stanford, CA 94305-5015 (


A three-stage model isolates conditions under which an executive appointment to a collective choice body, such as a court or a regulatory agency, has an immediate bearing on policy. The model strikes a balance between previous formal models that predict either excessive gridlock or excessive policy responsiveness as a consequence of the politics of appointments. I test the model using approximately four decades of data on U.S. Supreme Court appointments. Two hypotheses summarize the unique predictions of the model and are strongly corroborated. A third, less distinctive hypothesis about strategic judicial retirements is weakly supported.