The influence of amicus curiae briefs on the Supreme Court.

• Author: Kearney, Joseph D.

INTRODUCTION AND OVERVIEW

The last century has seen little change in the conduct of litigation before the United States Supreme Court. The Court's familiar procedures--the October Term, the opening-answering-reply brief format for the parties, oral argument before a nine-member Court--remain essentially as before. The few changes that have occurred, such as shortening the time for oral argument, have not been dramatic.

In one respect, however, there has been a major transformation in Supreme Court practice: the extent to which non-parties participate in the Court's decision-making process through the submission of amicus curiae, or friend-of-the-court, briefs. Throughout the first century of the Court's existence, amicus briefs were rare.(1) Even during the initial decades of this century, such briefs were filed in only about 10% of the Court's cases.(2) This pattern has now completely reversed itself. In recent years, one or more amicus briefs have been filed in 85% of the Court's argued cases.(3) Thus, at the close of the twentieth century, cases without amicus briefs have become nearly as rare as cases with amicus briefs were at the beginning of the century.

Attitudes within the legal community about the utility and impact of amicus briefs vary widely. Perhaps the most common reaction among lawyers and judges is moderately supportive. Amicus briefs, it is said, can provide valuable assistance to the Court in its deliberations.(4) For example, they can present an argument or cite authorities not found in the briefs of the parties, and these materials can occasionally play a critical role in the Court's rationale for a decision.(5) Alternatively, these briefs can provide important technical or background information which the parties have not supplied.(6) Those sharing this perspective can point to the frequent citation of amicus briefs in the Justices' opinions in support of the supposition that the Court often finds such briefs helpful.(7)

Other members of the legal community, however, offer a much more negative assessment of amicus briefs. For example, Chief Judge Richard Posner of the Seventh Circuit has written that the amicus briefs filed in his court provide little or no assistance to judges because they largely duplicate the positions and arguments advanced by the parties.(8) Those who share this assessment regard such filings as largely a nuisance--imposing unwarranted burdens on judges and their staffs with few, if any, mitigating benefits. According to those who harbor this negative assessment, the judicial system would be improved if amicus filings were prohibited or at least sharply curtailed.(9)

Justice Scalia recently offered a third perspective on the widespread filing of amicus briefs. The occasion was Jaffee v. Redmond,(10) where the Supreme Court recognized a "psychotherapist's privilege" under Rule 501 of the Federal Rules of Evidence. In a dissenting opinion joined in part by Chief Justice Rehnquist, Justice Scalia offered the following observation:

In its consideration of this case, the Court was the beneficiary of no fewer than 14 amicus briefs supporting respondents, most of which came from such organizations as the American Psychiatric Association, the American Psychoanalytic Association, the American Association of State Social Work Boards, the Employee Assistance Professionals Association, Inc., the American Counseling Association, and the National Association of Social Workers. Not a single amicus brief was filed in support of petitioner. That is no surprise. There is no self-interested organization out there devoted to pursuit of the truth in the federal courts. The expectation is, however, that this Court will have that interest prominently--indeed, primarily--in mind. Today we have failed that expectation, and that responsibility.(11) Justice Scalia's reference to "self-interested organizations" and his lack of surprise in finding no amicus arguing against creation of an evidentiary privilege suggest that amicus briefs reflect a form of interest group lobbying directed at the Court. His remarks further suggest, in keeping with the interest group theory of politics,(12) that well-organized interest groups will be more likely to file amicus briefs than will diffuse and poorly organized interests. Most significantly, Justice Scalia intimates that the over-representation of well-organized interest groups through amicus filings may have an influence on the outcomes reached by the Court. He at least suggests that this is what happened in Jaffee, in which the highly disproportionate amicus support for the respondent may have sent a clear signal to the Court that a decision recognizing a psychotherapist's privilege would more likely receive acclaim from organized groups than one rejecting such a privilege.

The critical but unstated variable that divides these different perspectives is the model of judicial decision making adopted by each commentator. Each of the three positions corresponds to a different model of judging, which in turn suggests a different pathway of influence that amicus briefs may have on the outcomes reached by courts.(13)

The first or moderately supportive view of amicus briefs implicitly adopts the conventional legal model of judicial decision making. Under this model, judges are regarded as seeking to resolve cases in accordance with the requirements of law, as understood by professional actors in the legal community. Amicus briefs are assumed to have an impact on this process insofar as they contain new information--legal arguments and background factual material--that would be relevant to persons seeking the correct result in light of established legal norms.

The second or sharply negative view is often associated with what political scientists call the "attitudinal model" of judicial behavior.(14) This model posits that judges have fixed ideological preferences, and that case outcomes are a product of the summing of the preferences of the participating judges, with legal norms serving only to rationalize outcomes after the fact. Under this view, amicus briefs should have little or no impact on the outcomes reached by a court, because each judge's vote in a case is assumed to be the product of his or her preestablished ideological preferences with respect to the issue presented. A judge can obtain all the information needed to determine his or her vote, the attitudinal model would suggest, by reading the "Question Presented" and the statement of facts contained in the parties' briefs. To the extent that amicus briefs provide additional legal arguments and factual background, under this model they offer information of no relevance to judges.

The third view, which we have extrapolated from Justice Scalia's comments in Jaffee, implicitly adopts an interest group theory of the judicial process. In contrast to the attitudinal model, the assumption here is that judges do not have strong ideological preferences about most issues. Rather, they are empty vessels who seek to decide cases so as to reach those results supported by the most influential groups in society that have an interest in the question at hand. Amicus briefs on this view should be important to the judicial process because of the signals that they convey about how interested groups want particular cases decided. If, as in Jaffee, the groups filing amicus briefs all want a case to come out a certain way, this tells the judges how to rule if they want to secure the approval of organized groups.

The question of how amicus briefs influence judicial outcomes is one as to which, in principle, empirical information can be gathered. Unfortunately, when courts devise policies regarding the filing of amicus briefs, and when lawyers advise clients about filing such briefs, they almost always proceed on the basis of anecdotal information or recent episodes that may be unrepresentative of the larger universe of amicus curiae participation. What is worse, this highly fragmentary information may be processed through a perceptual lens based on a particular implicit model of judging, which model, again, is untested and may or may not be a reliable guide to underlying realities.

In this Article, we present empirical evidence designed to enhance our understanding about the impact of amicus curiae briefs on the Supreme Court and therefore also about the validity of different models of judging. To this end, we have assembled a large database consisting of fifty years of Supreme Court merits decisions---every argued case from the 1946 Term through the 1995 Term. For each decision, we recorded, among other things, the outcome of the case, the number of amicus briefs supporting the petitioner, the number supporting the respondent, and whether certain key institutional litigants filed amicus briefs in the case.(15) We then analyzed these data using standard statistical techniques to try to differentiate between different hypotheses about the influence of amicus briefs on judicial behavior.

Briefly, our principal findings are as follows. First, our study shows conclusively that the incidence of amicus curiae participation in the Supreme Court has increased dramatically over the last fifty years. While the number of cases that the Court has disposed of on the merits has not appreciably increased during this time (indeed it has fallen in recent years), the number of amicus filings has increased by more than 800%.

In terms of the influence of amicus briefs on outcomes, our study uncovers a number of interesting patterns. We find that amicus briefs supporting respondents enjoy higher success rates than do amicus briefs supporting petitioners; that small disparities of one or two briefs for one side with no briefs on the other side may translate into higher success rates but larger disparities do not; that amicus briefs cited by the Court appear to be no more likely to be associated with the winning side than briefs...