Untangling Mixtures in Judicial Opinions

• In Event: Legal Texts

Abstract

Within the small deliberative voting body of the U.S. Supreme Court, prior work has regularly looked to the voting alignments of the justices in order to understand bargaining power and who exerts power over decision outcomes (i.e., who wins or loses). However, little consensus has emerged over who exerts control over the Court’s actual output -- judicial opinions -- with three schools of thought emerging: first, that the opinion author controls opinion content; second, that the median member of the court controls opinion content; or, third, and most recently, that the median of the majority coalition controls the content of the opinion. Instead, in this paper we look for influence where it theoretically operates -- in the opinions themselves -- and identify the unique contributions of separate justices to the collective output of the Court.

To do so, we build on a well-established tradition in text-as-data research on estimating authorship, and develop a model that leverages writing characteristics to predict the authors of individual sentences across more than five decades of Supreme Court decisions. Specifically, we utilize “uniquely” authored decisions (i.e., dissenting opinions authored by a single justice) and the other writings of individual justices in order to construct predictive models of justice writing styles. Consider, for instance, the uniqueness of former justice Antonin Scalia’s style, including his vocabulary (e.g., the use of rare terms like “argle-bargle”, “tutti-frutti”, or “gobbledygook”), grammatical patterns, use of precedent, and so on. By learning the characteristics of texts known to be authored individually by each justice, we construct a novel measure of opinion authorship and contributions well-suited for the study of bargaining power. To that end, we employ the measure to analyze the composition of co-authored opinions (notably, the majority opinion) and deduce the justices most responsible for opinion content. In all, our research offers insight not just into judicial behavior, but is also more broadly valuable in understanding the pivotal actors in small group bargaining situations.

Authors

• Justin H. Gross, University of Massachusetts, Amherst

• Doug Rice, University of Massachusetts