Preemption in the Rehnquist and Roberts Courts: An Empirical Analysis

This article presents an empirical analysis of the Rehnquist Court’s and the Roberts Court’s decisions on the federal (statutory) preemption of state law. In addition to raw outcomes for or against preemption, we examine cases by subject-matter, level of judicial consensus, tort versus regulatory preemption, party constellation, and origin in state or federal court. We present additional data and analysis on the role of state amici and of the U.S. Solicitor General in preemption cases, and we examine individual justices’ voting records. Among our findings, one stands out: over time and especially under the Roberts Court, lawyerly preemption questions have assumed a distinctly ideological flavor. Preemption cases are much more likely to be contested than they were in earlier decades; and in those cases, once-rare judicial bloc voting has become common