Abstract

The Supreme Court's reasoning in a decision, including the precedent it cites in support of that reasoning, can be as significant as the outcome in determining the long-term impact of a case. As a result, the content of opinions can be used to provide important new insights into existing debates regarding judicial politics. In this article we present a strategic content model of the judicial process, which demonstrates how opinion content results from the strategic interaction between justices during the Court's bargaining process. This is the first article to show on a large scale that the extent to which a majority opinion writer cites authoritative precedent is systematically influenced by the decisions and ideology of other justices. We find that the Court generates opinions that are better grounded in law when more justices write concurring opinions. This demonstrates that justices write concurring opinions based not just on a preference for making their opinions known, but also to influence the reasoning relied on by the majority opinion. We also show that diversity of opinion on the Court, a factor often overlooked in the political science literature, has a significant impact on the extent to which a Court opinion cites authoritative precedent. Finally, our results provide a novel test of the agenda-control and median-justice models. We find that the ideology of the median justice influences the citation of precedent in the majority opinion, whereas the majority opinion writer's ideology does not, suggesting that agenda-setting powers are not as strong as previously claimed.