Are judges political? At least in some ways, this is an empirical question. Together with Tom Miles and a group of superb students, and as part of the Chicago Judges Project, I have been studying this question in an area where the answer might well be expected to be "no." But the answer turns out to be “yes” -– if a somewhat qualified one.
The area is a bit esoteric; it involves judicial review of agency interpretations of law. Under the Supreme Court's decision in the famous Chevron case, courts are supposed to uphold agency interpretations of ambiguous statutes so long as those interpretations are reasonable. This principle -- which calls for judicial deference to agencies -- might well be expected to eliminate differences between Republican and Democratic appointees to the federal bench. But it doesn't. (An empirical paper on these questions, by Miles and me, will appear in the summer issue of the University of Chicago Law Review. A detailed paper on judicial review of executive decisions, mostly normative but also discussing the data, will appear in the Yale Law Journal.)
On the lower courts, we have studied all published court of appeals decisions between 1990 and the present, reviewing interpretations of law by the Environmental Protection Agency, the Federal Communications Commission, and the National Labor Relations Board. Decisions are generally coded as "liberal" if the agency decision is upheld against industry attack; decisions are also generally coded as liberal if the agency decision is invalidated as a result of an attack by a public interest group.
Here are some of our preliminary findings:
1. Republican appointees show significantly more conservative voting patterns than Democratic appointees.
2. When Republican appointees sit only with Republican appointees, and when Democratic appointees sit only with Democratic appointees, the gap grows -- by a lot. Republican appointees show far more conservative voting patterns when sitting only with other Republican appointees; the same is true for Democratic appointees on the liberal side.
3. Republican appointees are more likely to uphold the interpretations of Republican presidents than those of Democratic presidents. Democratic appointees are more likely to uphold the interpretations of Democratic presidents than those of Republican presidents.
What about the Supreme Court? Here we have studied the votes of the individual justices between 1990 and the present in all clear Chevron cases -- that is, in all cases in which the Court applies the Chevron framework. These are our main results:
1. Justices Scalia, Thomas, and Rehnquist show significantly higher deference rates under the Bush Administration than under the Clinton Administration. Justices Souter, Stevens, Breyer, and Ginsburg show higher deference rates under the Clinton Administration than under the Bush Administration. (The change in the latter group is smaller than in the former.)
2. In Chevron cases, Justices Scalia, Thomas, and Rehnquist show the most conservative voting patterns, while Justices Stevens, Souter, Breyer, and Ginsburg show the most liberal. This is noteworthy because under the Chevron framework, judges are supposed to accept reasonable interpretations of ambiguous law -- in a way that might be thought likely to "filter out” political convictions on the part of judges.
3. When a justice is voting to reverse an agency’s decision under Chevron, what is the likelihood that the agency’s decision will be liberal? For the Souter, Stevens, Breyer, and Ginsburg group, the likelihood is 33%; for the Rehnquist, Scalia, and Thomas group, the likelihood is 62%.
The upshot is that judicial convictions -- the policy preferences of judges -- appear to be playing a significant role in an area of the law in which such convictions are not supposed to be relevant.
This data should not be overread. The differences between Republican and Democratic appointees, while significant, are not huge. It would be foolish and wrong to say that the relevant decisions are simple products of politics. Republican appointees often uphold decisions by agencies under Democratic presidents, and vice-versa. Nonetheless, the role of judicial convictions is unmistakable. (This evidence fits well with the findings of a study of ideological voting in many contested areas of the law, published in the Virginia Law Review in 2004 and written by David Schkade, Lisa Ellman, and me.)
We hope to be posting our results before long.