Document Type


Publication Date



The federal preemption of state law has emerged as a prominent field of study for legal scholars and political scientists. This rise to prominence of a technical and often dull field of jurisprudence is due to a number of developments-increasingly frequent federal statutory preemptions; the states' unprecedented aggressiveness in regulating business transactions, the expansion of corporate liability under state common law and the increased resort of corporate defendants to federal preemption defenses; and, not least, the Rehnquist Court's discovery of federalism and states' rights.

Unfortunately, the preemption debate has been marred by misperceptions and a lack of reliable data. Extravagant attention has been lavished on a few landmark cases, which may not be a reliable guide to the preemption universe. Studies of judicial behavior in this area have relied on an inadequate empirical foundation.

This Article presents an empirical overview and a preliminary analysis of the Rehnquist Court's preemption decisions. Part II describes the case universe and the outcomes. Part III discusses the role of the Supreme Court-more precisely, the Court's perception of its own role-in preemption litigation. Part IV suggests that outcomes in preemption cases may be most readily explained as judicial responses to certain signals or "cues." Two signals in particular prove significant: the presence of a state as a party to a preemption dispute, and the position of the Solicitor General. State amicus briefs and the partisan affiliation of the Solicitor General (Democrat or Republican) may also affect preemption case outcomes; however, we cannot show either variable to be statistically significant

Part V examines the justices' votes in preemption cases and addresses the discontinuity between the Rehnquist Court's federalism cases and its preemption decisions. The Court's federalism decisions have, until very recently, worked a major doctrinal shift in federal-state relations, in favor of the states. That shift has been the work of a stable bloc of five conservative justices, who have carried the federalism banner against a bloc of four liberal justices. In preemption cases, in contrast, liberals often vote against preemption (and thus "for the states"), whereas conservative justices often flip-flop in the opposite direction. We find substantial evidence to buttress the impression of preemption cases as a mirror image of pure federalism cases. Unlike federalism law, however, preemption law shows no clear decisional trend. Moreover, we find no firm voting blocs and no swing vote.

The concluding Part VI re-examines the perceived discontinuity between the Rehnquist Court's federalism and preemption decisions in light of the evidence and argues that a satisfactory explanation of that phenomenon is bound to be more complicated than a simple "attitudinal" model of judicial behavior would suggest.


Federal Courts, Jurisprudence, Conflict of Laws

Publication Title

Supreme Court Review

Publication Citation

14 Sup. Ct. Rev. 43 (2006).