A good deal of scholarly evidence suggests that the decisionmaking of the U.S. Supreme Court is affected by legal argument. At the same time, it seems clear that in a great many cases the justices have enduring, strongly held views. In such cases, they should be impervious to the effects of advocacy. When are the justices apt to be influenced by the Court's legal community, and when will lawyers be less relevant? The answer, we think, has to do with the salience of the issue before the Court. We suspect that in nonsalient cases the justices have less-intense preferences and therefore are open to the persuasion of lawyers. In salient cases, by contrast, the content of legal policy matters much more to the justices. As a result, they are less amenable to legal argument and adhere more strictly to their personal policy preferences. Our empirical tests support this orientation.
The idea that the members of the U.S. Supreme Court can be affected by legal arguments is hardly new. At least as far back as the Marshall Court, there is evidence that the justices have been responsive to legal advocacy. In McCulloch v. Maryland (1819), for example, one of the Court's earliest repeat players, William Pinkney, sought to frame an interpretation of the Necessary and Proper Clause that was solicitous to the preferences of Chief Justice John Marshall; indeed, the chief justice found it so appealing that it was adopted wholesale into the Court's written opinion (White 1988:248-50). Of course, as a staunch Federalist, Chief Justice Marshall was doubtless sympathetic to any argument that favored expanding the reach and influence of the new national government. In fact, it was widely believed, even before the Court heard arguments in McCulloch, that the Marshall Court would support the existence and independence of the Bank of the United States (Warren 1922:508-9). Chief Justice Marshall may well have employed Pinkney's arguments in his written opinion, but given the chief justice's strong views on this issue of national prominence, it seems quite unlikely that Chief Justice Marshall would have declared the Bank unconstitutional, had the government's case been entrusted to the hands of a less-capable attorney. Did Pinkney actually influence Chief Justice Marshall, or did Chief Justice Marshall's opinion simply reflect his steadfast commitment to Federalist principles in a case where the legal and political stakes were especially high? This question, posed in a contemporary context, is the principal concern of this article.
Specifically, we posit that the impact of legal advocacy in the U.S. Supreme Court is conditioned by issue salience. Using available data from the Burger Court, we find that in salient cases-cases in which we presume the justices care a good deal about the outcome-legal advocacy carries no empirical weight. In nonsalient cases, by contrast, the justices still follow their policy preferences, but because they are less resolute about case outcomes, they are more amenable to legal persuasion. These results persist even after controlling for the preferences of the justices as well as their ideological sympathy for litigants of different status. We conclude that, when the justices' informational needs are high and the intensity of their predispositions is low, the members of the Court pay a good deal of attention to the competing visions of legal policy presented before them.
Scholarly Perspectives on Legal Arguments
Legal advocacy is generally regarded as a significant influence in the modern Supreme Court. For their part, members of the legal community view the justices as highly sensitive to the ideas and information contained in briefs and oral arguments (Baker 1996; Enns 1998; Ennis 1984; Stern et al. 2002; Sungaila 1999). Scholarly studies of the Court's litigators have long highlighted the vital role that lawyers play in formulating the law (Casper 1972; Vose 1957), and over the last decade a good deal of systematic evidence has suggested that the Court's policies are affected by legal advocacy. …