Confirmation Politics and The Legitimacy of the U.S. Supreme Court: Institutional Loyalty, Positivity Bias, and the Alito Nomination


  • This is a revised version of a paper delivered at the 64th Annual Meeting of the Midwest Political Science Association. This research has been supported by the Law and Social Sciences Program of the National Science Foundation (SES-0553156). Any opinions, findings, and conclusions or recommendations expressed in this article are those of the authors and do not necessarily reflect the views of the National Science Foundation. Additional funding for the 2006 survey was provided by the Mershon Center for International Security Studies of The Ohio State University (“The Legitimacy of the Supreme Court and Critical Nominations”), to whom we are much indebted. In addition, support for the 2005 survey was provided by the Atlantic Philanthropies in a grant to the Center for Democracy and the Third Sector (CDATS) at Georgetown University. The 2005 survey was also funded in part by the Weidenbaum Center on the Economy, Government, and Public Policy at Washington University in St. Louis. Marc Morjé Howard, with the assistance of James L. Gibson, was primarily responsible for executing that survey. We greatly appreciate Howard's untiring efforts on the 2005 project, as well as the support for this research provided by Steven S. Smith. We also appreciate the research assistance of Marc Hendershot and Christina L. Boyd, both of Washington University in St. Louis, and the comments of Jonathan To, Carissa van den Berk Clark, Amy Overington, Thomas G. Hansford, Barry Friedman, Lee Walker, and Jeff Yates on an earlier version of this article.

James L. Gibson is Sidney W. Souers Professor of Government, Department of Political Science; Professor of African and African American Studies; and Director, Program on Citizenship and Democratic Values, Weidenbaum Center on the Economy, Government, and Public Policy, Washington University in St. Louis, Campus Box 1063, 184 Seigle Hall, St. Louis, MO 63130-4899 (

He is also Fellow, Centre for Comparative and International Politics, and Professor Extraordinary in Political Science, Stellenbosch University (South Africa). Gregory A. Caldeira is Distinguished University Professor, Dreher Chair in Political Communications and Policy Thinking, and Professor of Law, Ohio State University, 2022 Derby Hall, Columbus, OH 43210-1373 (


Gibson, Caldeira, and Spence (2003a, 2003b, 2005) expound the theory of positivity bias in their analysis of the legitimacy of the U.S. Supreme Court in the aftermath of Bush v. Gore. This theory asserts that preexisting institutional loyalty shapes perceptions of and judgments about court decisions and events. In this article, we use the theory of positivity bias to investigate the preferences of Americans regarding the confirmation of Judge Samuel Alito as an associate justice of the Supreme Court. More specifically, from the theory of positivity bias, we derive the hypothesis that preferences on the Alito confirmation are shaped by anterior commitments to the Supreme Court. Based on an analysis of a national panel survey, we find that those who have a high level of loyalty toward the Supreme Court rely much more heavily on what we term judiciousness—in contrast to ideology, policy, and partisanship—in forming their opinions on whether to confirm Alito. Thus, institutional loyalty provides a decisive frame through which Americans view the activity of their Supreme Court.