Does Legal Doctrine Matter? Unpacking Law and Policy Preferences on the U.S. Supreme Court

Abstract

To understand and assess the impact that the law has on judicial decision-making on the U.S. Supreme Court, one must disentangle the effects of law and policy preferences. In this paper, we elaborate the fundamental character of this challenge, and then present a novel approach to measuring the effect - if any - of the law on justices' decisions. Key to our approach is the use of positions taken by political actors outside of the court who put less emphasis on legal considerations. The positions taken by these actors allow us to pin down policy elements of voting. We use these elements to identify statistically the effects of legal forces including adherence to precedent, judicial restraint in the form of deference to Congress and a strict interpretation of the First Amendment's protection of speech clause that may guide judicial decision-making. The evidence suggests that legal factors play an important role and that their effects vary across the justices in interesting ways.

Keywords: Decision-making, legal model, first-amendment, stare decisis, judicial restraint

JEL Classification: K40