Segal–Cover score

Segal-Cover scores attempt to measure the relative liberalism or conservatism of United States Supreme Court justices. Their method of computing ideology scores was introduced by Jeffrey Segal and Albert Cover in their article "Ideological Values and the Votes of U.S. Supreme Court Justices," published in the American Political Science Review in 1989. The initial scores from the 1989 article were updated by Segal et al. in 1995.

The scores are based on analysis of pre-confirmation newspaper editorials regarding the nomination of each justice. Since the scores are not based on judicial rulings or opinions, they are relatively exogenous to judicial behavior. However, Segal and Cover found that the scores were strongly correlated with the votes of the justices. The scores range from 0 (most conservative), to 1 (most liberal). A score of how qualified each judge is is also given, with 0 being unqualified and 1 being most qualified. The Segal-Cover Scores for some members of the Court are as follows (qualification on right):

Name	Score	Qualification
Ruth Bader Ginsburg	0.680	1.000
Stephen Breyer	0.475	0.545
Anthony Kennedy	0.365	0.890
David Souter	0.325	0.765
John Paul Stevens	0.250	0.960
Clarence Thomas	0.160	0.415
John Roberts	0.120	0.970
Samuel Alito	0.100	0.810
Antonin Scalia	0.000	1.000