ABSTRACT
Lawyers are wordsmiths, not number crunchers. Thus, quantitative or mathematical evidence has long been a source of bewilderment to the profession.1 Some years ago, a lawyer-statistician team, Michael Finkelstein and William Fairley, suggested a modest use of an elementary formula of probability theory, known as Bayes's formula, to aid jurors in assessing statistical identification evidence.2 In an eloquent response, Laurence Tribe argued against the proposal on two general grounds.3 First, he offered a variety of practical reasons to suggest that probabilities calculated according to the formula would not be as accurate or useful as they might, at first blush, appear. Second, he pointed out how values other than the accuracy of factfinding might be undermined by the explicit use of probability calculations, especially in criminal cases.4 In the succeeding years, no one took the Finkelstein-Fairley proposal very seriously, although the question is not as clear-cut as most people assume.5
