Does the Median Justice Control the Content of Supreme Court Opinions?

Abstract

A commonly-held view of Supreme Court decision-making is that the median justice on the Court controls the content of opinions. This view rests on an application of median voter theorem - typically applied to legislative decision-making or party positioning - in the judicial context. We argue that the judicial context often involves decision problems that differ from these more familiar applications of median voter theory in ways that make a straightforward application of the median voter theorem inappropriate. In particular, judges simultaneously vote on an outcome (the judgment) and sign onto a rationale (the opinion). We demonstrate that if judicial preferences across these two aspects of a case are discontinuous - that is, if justices do not switch their vote on the outcome in exchange for concessions on rationale - the median justice typically does not determine the content of Supreme Court decisions. We offer an alternative account of the location of influence on decision content. Finally, we offer empirical evidence that demonstrates the inadequacy of median justice theory, and suggests support for our alternative account.