"Beyond Reasonable Doubt" and "Probable Cause": Historical Perspectives on the Anglo-American Law of Evidence.

• Author: Tillers, Peter

INTRODUCTION

Revolutions are proclaimed more often than they occur. Nonetheless, we seem to be in the midst of a "probabilistic revolution."(1) This revolution goes beyond physics and Heisenberg's well-known Uncertainty Principle,(2) and it goes far beyond the relativistic nihilism of Critical Legal Studies. The probabilistic revolution extends to a wide variety of academic fields, including the social sciences,(3) decision theory,(4) biology,(5) economics,(6) logic,(7) and philosophy of science.(8) This revolution is not confined to the academy. For example, it has influenced the art of statecraft,(9) the conduct of war and business, the tactics of election campaigning,(10) and the practice of medicine.(11)

The Anglo-American law of evidence may have anticipated the probabilistic transformation of contemporary social and political life.(12) For quite some time - at least for 100 years and, if Professor Barbara Shapiro(13) is right, for at least 200 years - the governing assumption of this body of law has been that all or practically all facts are uncertain and that proof of facts is always or almost always a matter of probabilities.(14) Legal scholarship has also long emphasized the probabilistic nature of judicial proof.(15) In recent years scholarly interest in the topic of uncertain forensic proof has intensified. As the use of statistical evidence in courtrooms has increased, legal scholars have devoted more and more attention to formal theories of uncertainty. This "new evidence scholarship"(16) has generated a large body of literature on "trial by mathematics" and statistical evidence.(17)

Despite the long pedigree of probability in the law of evidence and in evidence scholarship, there are sharp disagreements today about the basic nature of forensic proof. Some legal scholars are deeply skeptical about, if not necessarily opposed to, the new evidence scholarship.(18) New evidence scholars themselves disagree about the nature of forensic evidence, inference, and proof.(19) Although the result has been a lively and interesting debate, some of the participants in this debate have staked out positions that appear to be irreconcilable. Sometimes the protagonists seem not even to understand each other. In situations such as this, it is often useful to consider how scholarly debates and discussions came to have the character that they do; a look into the past can put problems in a new light. Fortunately, in recent years scholars have produced several enlightening studies of the historical origins of our present-day conceptions of uncertainty and probability.(20) I had hoped that Shapiro's study of the origins of the law of evidence would shed still more light on the phenomenon of uncertainty. I regret to say that Beyond Reasonable Doubt did not live up to my expectations.

I. Historical Scholarship and Evidence Scholarship

Shapiro devotes a large part of her new book to the history of the reasonable doubt and probable cause standards in the "Anglo-American"(21) Criminal process. Shapiro calls her investigation "a member of the species intellectual history of which the history of legal doctrine is a subspecies" (p. 249). Thus, Shapiro examines the "intellectual baggage" that underlies the "talismans" of reasonable doubt and probable cause.(22) Shapiro's discussion of the origins and evolution of reasonable doubt and probable cause, however, is part of a more general historical argument. Shapiro maintains that a new empiricist philosophy crystallized in Britain late in the seventeenth century and made its presence felt in fields such as theology, natural science, history, and philosophy. She argues that this new empiricism (as well as other intellectual traditions) influenced the development of the Anglo-American law of evidence and that by the nineteenth century empiricist terminology and ideas dominated legal discourse about evidence. Beyond Reasonable Doubt describes how empiricist language and notions crept into legal literature. To show how empiricist language and principles gradually infiltrated and took over the law of evidence itself, Shapiro traces changes both in the criminal process and in a variety of legal doctrines.

The subject matter of Beyond Reasonable Doubt is vast. Building on her earlier work,(23) Shapiro surveys intellectual currents not only in the law, but also in fields such as science, religion, rhetoric, and philosophy. The geographical range of Shapiro's book is also wide. She discusses developments in Scotland, America, and Continental Europe as well as England. Furthermore, Beyond Reasonable Doubt covers a great deal of time. Shapiro's book emphasizes developments from 1500 to 1800, a period of three centuries. Shapiro also discusses matters such as trial by jury in the thirteenth and fourteenth centuries(24) and the Romano-canon legal tradition in the Middle Ages.(25) Altogether, Beyond Reasonable Doubt discusses developments over the course of more than half a millennium of Western history.(26)

The sweeping proportions of Beyond Reasonable Doubt may be justified. Shapiro's historiographical tastes run toward intellectual history. It is notoriously difficult to pinpoint the exact place or time of important changes in the "thinking" of a society(27) or culture; intellectual traditions often originate in distant times and places and broad intellectual currents ordinarily change slowly. Shapiro's preference for intellectual history, however, does not fully explain the scope of her investigation. Shapiro examines developments after 1800 as well as developments before 1500. Of course, no particular year can serve as a definitive marker of the end of an intellectual tradition; like old soldiers, intellectual currents fade away slowly. However, Shapiro discusses developments that occurred long after 1800. For example, she considers the U.S. Supreme Court's treatment of probable cause in the 1980s (p. 147). Because Shapiro peers into the present as well as into the past, it is fair to infer that Shapiro wants to throw light on contemporary problems in the law of evidence as well as on the historical origins of the law of evidence.

The history of the law of evidence is an unjustly neglected field of scholarship. Shapiro's earlier work has already done much to fill this void.(28) Beyond Reasonable Doubt appears to be another important addition to scholarship in the history of the law of evidence. Shapiro's discussion of the intellectual background of the modern law of evidence contains a wealth of interesting detail, much of which is new to me. For example, I first learned from Shapiro about the possible influence of both the rhetorical tradition and English religious casuistry on the early English law of evidence.(29) Moreover, Shapiro's explanation of the medieval view of presumptions (pp. 213-41) is useful for amateur legal historians like myself who occasionally forage in older English reports for interesting discussions of evidence. However, since I am only an amateur in matters historical, I am not in a position to make a definitive judgment about Beyond Reasonable Doubt as a work of historical scholarship. Hence, in this essay I focus on the significance of Beyond Reasonable Doubt for contemporary evidence scholarship; I say little about its significance for historical scholarship.

My attitude of agnosticism about the extent of Shapiro's contribution to historical scholarship is not disingenuous; although I believe that Beyond Reasonable Doubt adds little to our understanding of contemporary problems of evidence and proof in the law or to our understanding of the nature of evidence and proof in general, I believe that my critique of the theoretical dimensions of Shapiro's book does not necessarily call into question Shapiro's contributions to legal and intellectual history. Nonetheless, my critique of Beyond Reasonable Doubt may speak to the nature of Shapiro's contributions to historical scholarship.

Although Shapiro's main interest is intellectual history and Beyond Reasonable Doubt is generally "short ... on institutions" (P. 251), Shapiro does dabble in the history of legal institutions; she asserts that her general findings lie "at the boundary between intellectual and institutional history" (p. xv). As I explain in the remaining parts of this essay, Shapiro's theoretical arguments in Beyond Reasonable Doubt are unsatisfactory because they rest on theoretically unsophisticated notions about the nature of evidence, inference, probability, and proof. In one respect, the theoretical shortcomings of Beyond Reasonable Doubt affect Shapiro's historical arguments as well as her theoretical claims; they throw into question Shapiro's analysis of the causal relationship between institutional change and changes in the law of proof. Shapiro's discussion of the historical connection between the Anglo-American law of evidence and the institution of the trial jury is a case in point.

Shapiro explains the emergence of rules of evidence in criminal trials in England not by reference to intellectual currents and traditions, but by reference to changes in the way that the jury was expected to work. The modern trial jury is a passive body. It is not permitted to conduct its own investigation. It is not even permitted to make use of evidence that individual jurors chanced to acquire before they became jurors; generally speaking, the jury is permitted to consider only the evidence submitted by the parties at the trial. According to Shapiro and other historians, the medieval English trial jury was a "self-informing" body (p. 4). It was permitted and expected to conduct its own investigation, and it was permitted and expected to consider evidence and information within the personal knowledge of members of the jury. The idea that jurors may consider only the evidence that the parties present at trial was a later development, one that is completely antithetical to the medieval conception...