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

University of California Press

This chapter traces the development of the "beyond reasonable doubt" standard that has characterized the Anglo-American criminal justice system for more than two hundred years. That system has always depended heavily upon the jury so that any study of reasonable doubt necessarily must be linked to an examination of the jury. From the surviving records, it does not appear that judges initially concerned themselves much with the question of the jury's evidentiary duties. Early jurors reached decisions on the basis of a mixture of their own personal knowledge of events and the testimony of others. By the sixteenth century most of the personal knowledge had dropped away. Once jurors were clearly perceived to be reaching decisions on the basis of evidence presented in court, judicial charges to juries came to emphasize the duty of jurors to reach some sort of firm assurance of guilt based on the evidence. The formulations in these charges are of central concern to us here.

Sixteenth-, seventeenth-, and eighteenth-century judges faced a difficult task in telling juries what standards they should employ in reaching their decisions. The earlier common law offered no particular guidance. For reasons that we shall examine later, civil and ecclesiastical sources did not initially prove very useful. As a

result, the judges had little choice but to borrow from the epistemology that could be drawn from religious doctrine and philosophy. If judges felt they now had to instruct jurors on how to know about matters of fact and on how much to know, it was natural for them to turn to the ideas of their contemporaries who were principally concerned about knowing and who were attempting to convey their ideas about knowing to the lay population from which juries were drawn. This tendency was reenforced by the relative isolation of the judges from their normal source of professional sustenance, the bar, when dealing with jury matters. In normal circumstances, lawyers appeared for neither side in ordinary criminal cases.

In the course of the seventeenth century, English religious intellectuals engaged in many controversies that required them to develop intellectually and religiously satisfying grounds for decision making. Their efforts were both shaped and complemented by the enormous upsurge in epistemological thinking that was a part of what is commonly called the "scientific revolution." Thus the judges confronted twin sources of epistemological guidance. One was the English religious tradition, particularly the casuistical tradition, which sought a rational method of decision making in everyday life. The other was the scientific movement of Bacon, Boyle, and especially Locke and the empirical philosophers, who sought to establish scientific truth from the evidence they gathered. This chapter is about how judges created the beyond reasonable doubt standard for the jury, and so it is also about the religious and philosophical thinking from which that standard was derived.

There are two kinds of rules of evidence in common-law jurisdictions. The first, which deals with what kinds of evidence may get to the jury when and in what form, can be understood without much reference to nonjury developments. The second deals with the evaluation by the jury of the evidence, and how it is to decide whether there is sufficient probative evidence to justify a verdict. Such rules are drawn from the culture's general understanding of how we "know" things to be true. This chapter deals with this second variety and its relation to epistemological developments in seventeenth-century England.

The seventeenth-century intellectual crisis, however, was not the first to influence this body of rules. A much deeper crisis occurred during the twelfth century, when "irrational proofs," such as trial by ordeal, could no longer be seen as consistent with justice or with how truth determinations ought to be made. "Irrational proofs" were replaced on the Continent by the Romano-canon inquisition process, and in England by the jury trial.

The "rational" system of proof of the Romano-canon inquisition process provided a system of inquiry operated by professional judges. It was designed to obtain "full proof," defined by clearly established evidentiary standards which rigidly specified the quality and quantity of proof. A specified number of witnesses were required to prove facts, and once "full proof" had been achieved conviction was automatic. The judge in most criminal cases was essentially an accountant who totaled the proof fractions. Criminal cases, for example, required two good witnesses or confession. Because confession was of a particularly high evidentiary value, torture was used to assist in producing it. Complex rules determined whether there was sufficient evidence to justify judicial torture. Because the philosophical components in the Romano-canon system had been provided by late medieval scholastic philosophers, and because the system had become well entrenched on the Continent during that period, it seems to have been relatively uninfluenced by the epistemological issues that became acute in the early modern periodissues that would focus on the sources, nature, and limitations of human knowledge.

In England irrational proofs were replaced by the jury trial, which for several centuries required little in the way of rules of evidence or doctrinal standards for conviction. Despite a good deal of research, we still do not know a great deal about early trial juries. The abolition of the ordeal resulted in a dual system of presentment and trial juries. The accusing, or presentment, jury had developed before the abolition of ordeals in 1215. Originally it had sent those it considered appropriately accused to be tried by ordeal.1 The verdicts of these early presenting, or "medial," juries were more statements about a defendant's character than about his factual guilt

or innocence. The verdicts of the new convicting juries, which Roger Groot dates from c. 1219 to 1221, were "assertive" rather than evidentiary.2 Although originally there was some overlap in the membership of the two juries, the separation of the presentment and the trial jury was well advanced by c. 1328.3 Jurors, men of the neighborhood, were assumed to know the facts and to incorporate their own knowledge in their verdict. Juries thus arrived at findings of fact guided by common sense and common knowledge.

Recent research is modifying the traditional view that the medieval jury was entirely self-informing. It now appears that some jurors lived too far from the scene of the crime to have had firsthand knowledge of events. At least in private actions witnesses were examined occasionally. Verdicts were probably made on the basis of what was deemed to be personal knowledge of the facts, but that knowledge might be based on firsthand knowledge or derived from persons the jury believed. In the thirteenth and fourteenth centuries, trial jurors probably were both gatherers and weighers of evidence. Witnesses do not seem to have...