Vol. 9 No. 12 (December 1999) pp. 563-565.
MAJORITY RULE OR MINORITY WILL: ADHERENCE TO PRECEDENT ON THE U.S. SUPREME COURT by Harold J. Spaeth
and Jeffrey A. Segal. New York: Cambridge University Press. 1999. 359 pp. Cloth $59.95.
Reviewed by James F. Spriggs, II, Department of Political Science, University of California, Davis.
In MAJORITY RULE OR MINORITY WILL, Harold Spaeth and Jeffrey Segal provide a much-needed rigorous empirical
examination of the influence of precedent on U.S. Supreme Court justices' decisions. Although many legal scholars
and political scientists suggest that precedent constrains justices' choices, few systematic empirical studies
provide evidence either supporting or refuting this claim. Indeed, one of the key debates in the field of law
and courts is whether, why, to what extent, and under what conditions legal norms, such as stare decisis, affect
judges' decisions. To address this larger debate, Spaeth and Segal seek to answer the following question: doesprecedent
cause justices to make decisions they would otherwise not choose? In particular, they set out to determine whether
precedent compels justices to act contrary to their policy preferences. Using an imaginative and systematic research
design and a sample of cases drawn from the entire
history of the Court, Spaeth and Segal produce an important work that is sure to spark renewed focus on the legal
model of judicial decision making.
In chapter one, Spaeth and Segal describe three broad conceptions of the influence of stare decisis. First, the
"precedentialist" school of thought encompasses scholars, such as Ronald Dworkin, who view precedent
as an integral, if not primary, motivation for court decisions. Second, "legal moderates" consider precedent
to be one of many factors that influence judicial decision making. Finally, "preferential models" (such
as the attitudinal model or critical legal theory) argue that precedent exerts little to no influence on judges'
decisions. In the remainder of the book, Spaeth and Segal seek to understand which of these overarching points
of view garners empirical support. They ultimately conclude that their data most clearly support the preferential
model of decision making.
Chapter two carefully defines the research design and decision rules used by Spaeth and Segal to determine whether
(and to what degree) precedent motivates the justices' decisions. They define influence as requiring a person
to make a decision he or she would otherwise prefer not to make. This definition requires Spaeth and Segal to
first determine a justice's preference over an issue and then examine whether the justice later acts contrary to
that preference due to precedent. To do so, Spaeth and Segal assume that a justice's dissenting vote represents
opposition to the establishment of the precedent in a case. If a justice subsequently supports
a precedent from which he or she originally dissented then Spaeth and Segal infer that the precedent influenced
the justice's vote.
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The development of their data occurs in three steps. First, Spaeth and Segal select a set of cases that serves
as the precedents in their analysis, consisting of all of the Court's "major decisions"-- as listed in
Congressional Quarterly's Guide to the U.S. Supreme Court -- and a random sample of all other cases decided between
1793 and the present. Second, they identify the progeny of each of these precedents. They locate progeny by using
SHEPARD'S CITATIONS (via Lexis), which provides a list of all opinions citing a previously decided case. Spaeth
and Segal provide a comprehensive explanation for precisely how they determine whether a case is the progeny of
a precedent. They essentially treat as a progeny any orally argued case whose issue and factual circumstances
closely resemble those of the
precedent. In the end, the 341 precedents in their analysis resulted in a total of 1,206 progeny (for a total
of 2,425 votes cast by 77 justices). Third, Spaeth and Segal determine whether a justice's vote in a progeny resulted
from preference or precedent. This step entailed their reading each progeny and coding each justice's vote on
a six-point ordinal case - strong precedential, moderate precedential, weak precedential, weak preferential, moderate
preferential, or strong preferential. Strong and moderate precedential votes require a justice to write or join
an opinion that specifically supports the precedent from which the justice originally
dissented. A weak precedential vote is one in which the justice simply supports the direction of the precedent.
The strength of preferential voting follows a similar pattern. The coding protocols are explained in explicit
terms, and the tables contain a list of the progeny and the coding of each justice's vote. This level of detail
permits a reader to examine readily any of the coding decisions, though the coding scheme's reliability would have
been bolstered by an intercoder reliability analysis.
The bulk of the book, chapters three through eight, contains chronological in-depth analyses of the justices' votes
in the progeny cases, starting with the Jay Court and concluding with the Rehnquist Court. Each chapter generally
begins with sections discussing the historical context of the Court and describing the justices' votes in the progeny
cases. A subsequent section then details the extent to which the justices' votes resulted from preferences or
precedent. The findings are too rich to detail here, but one overarching conclusion pervades the analysis: justices
generally vote based upon preferences, not precedent. Only 11.9 percent of the justices' votes resulted from precedent.
At the individual level, Spaeth and Segal show that no justice can be labeled as a "precedentialist"
(i.e., a justice who voted for precedent more than 66.7 percent of the time). Five justices voting records, though,
appear consistent with expectations of the "legal moderates" (i.e., voting in favor of precedent between
33.3 percent and 66.7 percent of the time), including Lewis Powell in landmark cases and John Paul Stevens in ordinary
cases. In short, the data demonstrate that most justices' votes resulted from their policy preferences. For
example, Justice Douglas voted consistent with his policy preferences in 99.3 percent of the cases, and Chief Justice
Rehnquist did so in 94.8 percent of cases.
Although this book's primary goal is to determine whether (rather than why or under what circumstances) precedent
influences justices' behavior, the final chapter briefly attempts to explain the observed variance in precedent-based
votes. Specifically, Spaeth and Segal argue
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that precedential behavior should be more likely to occur in low-salience cases. Their data show, for example,
that while justices voted to follow precedent in 10.0 percent of the progeny of landmark cases, they did so in
17.6 percent of ordinary cases. While a plausible hypothesis, I raise a couple of issues. First, I suspect that
the conditions under which precedent constrains justices' decisions are more complex than whether the precedent
was salient. For example, one might expect that such factors as the current vitality of a precedent, the nature
and relevance of litigants' legal arguments, and bargaining among the justices might enter into a
justice's calculation regarding the use of a precedent. Second, the concept of case salience, and the underlying
reasons why it influences justices' decisions, can be slippery. For instance, the legal model would most likely
predict that case salience has an effect opposite that posited by Spaeth and Segal. The logic would be the following:
justices follow precedent in part because it both encourages future justices to adhere to their precedents and
maximizes the legitimacy of the Court. One would therefore expect justices to be more constrained when deciding
salient cases, and thus more likely to follow precedent, because their actions are more visible. In the end, I
am confident that the empirical results in this book will foster the research necessary to lay bare the causal
relationship between precedent and judicial
decision making.
The strength of this book rests in its empirically rigorous approach to studying precedent. Spaeth and Segal provide
a clear definition of the influence of precedent and offer detailed coding protocols for how they measured it.
Their data quite clearly indicate that, given their definition of precedent, justices' generally vote based on
their policy preferences. On this score, MAJORITY RULE OR MINORITY WILL represents a major advance over existing
scholarship and will have a lasting impact on the way scholars think about precedent. In particular, this book
will encourage researchers to examine this question using different conceptualizations and measures of the influence
of precedent. In doing so, future research will generate a more precise understanding of how precedent influences
judicial decision making
and the development of the law. My final assessment is that this book is a must read for anyone interested in
precedent, the Supreme Court, or judicial decision making.