Book Reviews
At long last, there is a systematic examination of the impact of the law on the decisions of the justices of the U.S. Supreme Court. For quite some time, political scientists have debated the influence of legal considerations on judicial behavior. In the absence of testable hypotheses, however, the conclusions reached have perhaps been more a product of conviction than empirical evidence. Enter Harold J. Spaeth and Jeffrey A. Segal, arguing that at least one feature of the legal model—stare decisis—can be operationalized and tested.
Precedent is, after all, a key component of the legal model, and, if their written opinions are any indication, the members of the Court accord their prior decisions a good deal of respect. The problem, of course, is that a seeming reliance upon precedent may be nothing more than a convenient post hoc rationale. For precedent to exercise an effect on the justices, say Spaeth and Segal, it must lead them to make decisions they would not otherwise have made. To that end, they argue that the justices who dissent in precedent-setting cases should alter their behavior by supporting those precedents when they are applied to later cases. Examining a large sample of both landmark and ordinary decisions, the authors develop a scale that measures degrees of adherence to precedent for dissenting justices. With these data, they come to a simple conclusion: stare decisis simply does not matter.
Beginning in 1793, Spaeth and Segal move carefully through the entire history of policy making on the Court. Despite important changes in the role of the Court, its substantive policies, and its institutional norms, the justices demonstrate a consistent unwillingness to abandon preference-based behavior. Clearly and convincingly, the book reveals that the members of the Court, ever since the inception of the republic, have been steadfast in their refusal to abide by decisions that they initially rejected. In fact, nearly 90% of their subsequent votes remain unaffected by the dictates of stare decisis, a figure that does not vary substantially across 200 years of judicial opinion.
Quite importantly, the data permit the authors to target, within more recent years, specific legal issues—abortion, civil rights, criminal procedure, death penalty, federalism—and this exercise serves only to buttress their more general claim. The consistent failure to conform to precedent, not only across but within individual areas of legal policy, is strong evidence that their overall findings do not cloud important relationships that might exist within certain areas of the law where idiosyncratic legal rules arguably govern case outcomes.
Aside from the power of these contemporary data, one of the other great strengths of the book is that it ambitiously cuts a wide temporal swath. The early chapters, in particular, provide a fascinating study of the politics of the high court during the nineteenth century, leaving little doubt that the earlier justices were no more guided by precedent than their modern-day counterparts. It is, in my view, the best evidence we have that preference-based models of judicial choice have broad historical application.
If there is a weakness of the book, it is that it comes to a conclusion that is not especially surprising. That is, the authors set out to test a hypothesis that so far as I can tell, few really believe. Most observers would probably be surprised if dissenting justices later modified their behavior to any substantial degree. What is fascinating is that the justices occasionally do exactly what Segal and Spaeth say they must do if they are affected by the law: they show strong respect for precedent. Justices in dissent in original decisions later acquiesce and acknowledge, sometimes explicitly, that they are bound by the authority of precedent. Why? Curiously, the authors display a breezy indifference to accounting for such behavior. Almost as an afterthought, Spaeth and Segal examine a few likely suspects, none at any great depth. That a precedent can alter one out of every ten dissenting votes does not strike me as trivial. I was left wondering why this occurs as often as it does.
Tables vie with text for space in this book, and readers who are not enthralled at the prospect of having crosstabulations described in considerable detail may find this volume somewhat less than electrifying. Nevertheless, those who consider the sum total of its evidence will find a compelling empirical case that speaks with considerable force to one of the long-standing debates in judicial politics. Stare decisis may well play a role in the Supreme Court, but this role, as many have long suspected, is scarcely a prominent one.
