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Unpublished Paper
The Partisan Dimensions of Federal Preemption in the United States Courts of Appeals
ExpressO (2010)
  • Bradley W. Joondeph, Santa Clara University School of Law

This paper explores some of these empirical uncertainties surrounding the political dimensions of preemption in the federal courts. More concretely, it presents a statistical study of every preemption decision rendered by the United States Courts of Appeals from January 1, 2005, to December 31, 2009, a total of 560 decisions and just over 1,700 judicial votes. And these data tell a story consisting of two distinct parts. The first part is that preemption disputes seem to produce a large measure of judicial consensus. In the full universe of cases, there is only a slight difference between Republican and Democratic appointees: Republican judges voted for outcomes favoring the preemption of state law at a rate exceeding Democratic judges by a margin of roughly 2.6 percent overall, and roughly 5 percent in published decisions. While these differences may not be trivial, they are not statistically significant.

The second part of the story is that, despite this general consensus, there remains an important difference between Republican and Democratic appointees. Specifically, in the most contested preemption cases—those in which at least one Republican and one Democrat served on the panel, and at least one judge dissented—Republican appointees were more than three times as likely as Democratic appointees to vote in favor of preemption (roughly 73 percent versus 21 percent).

Thus, the complete picture of preemption decisions in the Courts of Appeals is intriguing, if somewhat unsurprising. As a general matter, preemption cases do not provoke much fissure among federal circuit judges; the vast majority of cases are decided unanimously, such that a judge’s party affiliation lacks much value in predicting how she will vote in the randomly selected case. But in particular circumstances—especially the small subset of preemption cases where judges disagree on the result—party affiliation appears to be highly predictive of how that disagreement will play out. In these marginal cases—where the accepted sources of legal authority fail to control the outcome, and the norms of consensus and collegiality among circuit judges are insufficient to restrain dissent—the pattern is unmistakable: Republicans are far more likely than Democrats to favor the federal preemption of state law.

  • Preemption,
  • judicial politics,
  • constitutional development
Publication Date
July 23, 2010
Citation Information
Bradley W. Joondeph. "The Partisan Dimensions of Federal Preemption in the United States Courts of Appeals" ExpressO (2010)
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