Peter Enns (Cornell) and Patrick Wohlfarth (University of Maryland) have a forthcoming article (ungated) in the Journal of Politics that makes a similar point to the one I made in a blog post earlier today, except that it is based on real data and analysis. Below is the abstract:
In the Supreme Court’s most closely divided cases, one pivotal justice can determine the outcome. Given this fact, judicial scholars have paid substantial attention to the swing justice. This paper makes two theoretical contributions to the study of the swing justice and this justice’s resulting inﬂuence on case outcomes. First, we show that in a substantial number of cases, the justice that casts the pivotal vote is not the median justice on the Court. Second, we argue that the swing justice will typically rely less on attitudinal considerations and more on strategic and legal considerations than the other justices on the Court. The analysis suggests that even among the Court’s most closely divided decisions, which are typically thought to reﬂect the Court’s most ideologically driven outcomes, the pivotal swing vote is signiﬁcantly less likely to reﬂect attitudinal predispositions and more likely to reﬂect strategic considerations, such as the public’s preferences, and case–speciﬁc considerations such as the position advocated by the Solicitor General. The theory and ﬁndings suggest that a failure to consider the unique behavior of a pivotal actor—whether on the Supreme Court or any other decision making body—can lead to incorrect conclusions about the determinants of policy outputs.