This Article explores which legal precedents judges choose to support their decisions. When describing the legal landscape in a written opinion, which precedent do judges gravitate toward? We examine the idea that judges are more likely to cite "friendly" precedent. A friendly precedent, here, is one that was delivered by Supreme Court Justices who have similar political preferences to the lower court judges delivering the opinion. In this Article, we test whether a federal Court of Appeals panel is more likely to engage with binding Supreme Court precedent when the political flavor of that precedent is aligned with the political composition of the panel.
We construct a unique dataset of 591,936 citations to United States Supreme Court decisions by the federal Courts of Appeals in 127,668 unanimous decisions from 1971 to 2007. We find that judges gravitate toward friendly precedent. The political composition of a panel consistently influences which binding precedent is cited in the written opinion. All Republican-appointed panels gravitate toward the most conservative precedent; all Democratic-appointed panels gravitate toward the most liberal precedent and unfavorably cite the most conservative precedent. This result is notable because it provides strong evidence that judges, when reasoning their decisions, have different conceptions of binding precedent.
TABLE OF CONTENTS INTRODUCTION I. EXISTING LITERATURE ON PRECEDENT II. DATA A. Our Dataset B. Measures of Ideological Content of Precedent C. Summary Statistics III. RESULTS A. Friendly Precedent B. Unfriendly Precedent IV. DISCUSSION CONCLUSION INTRODUCTION
Imagine that you are invited to a party. Upon entering a crowded room, you see people that you know and like, those you know but dislike, and still others whom you do not even know. To whom do you gravitate? Do you converse with your existing circle of friends? Do you exchange pleasantries with your adversaries? Do you strike up conversation with strangers?
This familiar hypothetical is the motivation for this Article examining judicial behavior. (1) When a judge writes an opinion, she will see binding precedent from judges whom she likes, and other precedent from judges with whom she may not see eye-to-eye. Which precedent does a judge gravitate toward when writing the opinion? In this Article, we examine the idea that a judge will gravitate toward citing friendly precedent. Friendliness, here, is measured in terms of similar political preferences. Specifically, we test whether a federal Court of Appeals panel is more likely to engage with binding Supreme Court precedent when the political flavor of that precedent is aligned with the political alignment of the panel.
Since at least the early twentieth century, legal scholars have sought to understand how judges decide cases. Within jurisprudence circles, the debate pitted formalism against realism: formalists argued that legal problem-solving was a deductive process contained within the rules themselves; (2) realists rejected the centrality of rules in favor of nonlegal factors, including pragmatism. (3) The interdisciplinary debate has largely focused on whether judges act in accordance with their own ideological preferences (4) or are constrained by higher courts (5) or other political branches. (6) More recently, scholars have taken a middle view that judges are influenced by both legal and political factors. (7)
In exploring this question, interdisciplinary scholars have looked primarily at voting behavior. Their consensus is that judicial ideology influences how Supreme Court Justices (8) and lower federal court judges decide cases (9) alike. For example, the political leanings of federal Courts of Appeals judges-as measured by the party of the president who appointed the judge-are highly correlated with the ideological direction of their decisions. (10) "Ideological dampening" occurs when the three-judge panel is made up of judges appointed by both political parties: a liberal judge moderates a conservative majority; a conservative judge moderates a liberal majority."
This focus on outcomes, while certainly important, fails to capture a crucial aspect of judicial behavior. It completely overlooks the broader importance of the written opinion. These opinions provide guidance to judges and prospective litigants. (12) Case outcomes, by themselves, are limited in informing how judges will decide future cases. As Jack Knight has argued, scholars need to look at "aspects of the opinions accompanying the votes." (13) Legal precedent serves as the means by which judges validate their decisions and persuade other jurists (and lawyers) to adopt their point of view. (14)
The relationship between judges' ideology and their use of precedent has been relatively unexplored by scholars in law and political science. When reasoning their decision in a given case, do judges vary from one another in how they perceive and use binding precedent? Two competing hypotheses emerge. The first is that judges, irrespective of their ideology, draw upon the same corpus of precedent, but may differ in their interpretation and the conclusions they reach. The second is that, depending on their ideology, judges draw upon different subsets of precedent to explain their decisions. To return to the party metaphor, the former posits that judges work their way around the room; the latter contends that they talk mostly with their friends.
In this Article, we examine how judges in the Courts of Appeals cite Supreme Court precedent. We construct a unique dataset that includes every published unanimous federal appellate decision from the period 1971 to 2007. Specifically, the dataset contains every cited Supreme Court precedent for the years 1953 to 2007. Our dataset comprises nearly 130,000 unanimous Courts of Appeals opinions and nearly 600,000 citations to Supreme Court precedent. (15) We assign ideological scores to each precedent, using competing measures and methodologies, and distinguish whether judges are citing each precedent favorably (following) or unfavorably (distinguishing or criticizing).
Our central finding is that panel composition consistently and systematically influences which precedents appear in majority opinions. On average, panels comprised of three Democratic-appointed judges (DDD) favorably cite the most liberal ideological precedent. The addition of each Republican-appointed judge to the panel produces favorable citations to more conservative precedent, with a panel of three Republican-appointed judges (RRR) citing the most conservative precedent. The effect also occurs when examining the individual judge authoring the unanimous opinion: Republican-appointed authors cite more conservative precedent than Democratic-appointed authors.
Panel composition similarly influences judges' use of unfavorable Supreme Court precedent. Panels of all Democratic-appointed judges criticize or distinguish the most conservative precedent. As more Republican-appointed judges are selected to sit on the panel, the panel criticizes and distinguishes increasingly more liberal precedent. Panels of all Republican-appointed judges criticize or distinguish the most liberal precedent.
Judges have a great deal of discretion over which binding precedent to cite and significant leeway in determining how to justify their decisions and how to tailor their written opinions. (16) In much the same way that one might gravitate toward friends when entering a party, judges gravitate toward friendly precedent when writing judicial opinions. Our findings are notable because they provide strong evidence that different judges have different conceptions of which precedents are binding. Further, when judges restrict analysis in their opinions to certain friendly binding precedent, they may create two distinct echo chambers in case law.
Our Article proceeds as follows: Part I provides a brief literature review on legal precedent. Part II discusses the construction of our new dataset. Part III describes our results. Part IV discusses the implications of our findings--specifically, the practical relevance of precedent for the development of the common law. The final Section summarizes and concludes.
EXISTING LITERATURE ON PRECEDENT
As a formal matter, judges are bound by legal precedent. (17) Adherence to precedent, or stare decisis, provides the foundation of the common law. Judges may prefer to follow only their own precedent, but they realize that the import of their own decisions rests on their fellow jurists recognizing the relevance and persuasion of those decisions. (18) In this regard, opinions are a repeated game in which judges collectively benefit from a mutual respect for the common law. (19) This behavior is borne out empirically: when deciding cases, judges consistently acknowledge the importance of precedent. (20)
At the same time, judges have considerable discretion when writing opinions. (21) This discretion extends to the selection of which precedents are cited in a written opinion. Karl Llewellyn described judicial selection of precedent as involving two contradictory pursuits: freeing oneself from unwelcome precedent while "capitalizing welcome precedents." (22) For Llewellyn, judges navigate through existing precedent, selectively choosing the precedent that best supports their decision. (23) Jerome Frank similarly wrote that "[t]he judge, in determining what is the law of the case, must choose and select, and it is virtually impossible to delimit the range of his choice and selection." (24) Even if the same precedent were cited in a decision, judges may treat the precedent differently--that is, favorably or unfavorably. Herman Oliphant wrote, "Each precedent considered by a judge ... rests at the center of a vast and empty stadium. The angle and distance from which the case is to be viewed involves the choice of a seat.... [The judge] can and must choose." (25)