Exaggerated and misleading reports of the death of conditional relevance.

• Author: Tillers, Peter
• Position: Response to article by Richard D. Friedman in this issue, p. 439

I

In 1980 the late Professor Vaughn C. Ball of the University of Georgia published an article called The Myth of Conditional Relevancy.(1) Ball's article is widely admired. One well-known evidence scholar, Ronald J. Allen, liked Ball's article so much that he borrowed its title word for word.(2) Although the extent of Allen's enthusiasm for Ball's analysis may be unmatched, a good number of students of evidence -- including this writer -- have said that Ball's analysis of conditional relevance is both original and important.3 Richard Friedman, by contrast, cannot be counted as one of Ball's more ardent admirers. Although Friedman does show due respect for Ball in his article in this issue of the Michigan Law Review,(4) he also finds fault with some parts of Ball's argument.

Friedman's article is an important one. It is important in part precisely because Friedman's view of the problem of conditional relevance and conditional probative value is distinctive.(5) In addition, Friedman's article effectively serves as a timely reminder of a fundamental property of inference from evidence in the judicial process, namely, the hierarchical or chain-like character of factual inference in contexts such as adjudication. Friedman's argument about how judges should be directed to handle challenges to the admissibility of conditionally relevant and conditionally probative evidence is likely to provoke a new round of much-needed scholarly debate about the more general and very important question of how the law should deal with the ineluctable phenomenon of hierarchical inference.

II

Friedman's article needs to be considered in context. The starting point is Ball's truly seminal 1980 article. Professor Ball was apparently a blunt fellow. He argued that the doctrine of conditional relevance is incoherent and unmanageable and that we ought to get rid of it. Friedman's general view of the conditional relevance doctrine is rather different from Ball's. Although Friedman agrees with Ball that the doctrine as it stands has flaws, he also sees a core of good sense in it. Hence, instead of arguing that the doctrine ought to be abolished, as Ball proposed, Friedman favors modifying it.

Friedman is clearly right about one thing: there is a core of good sense in the conditional relevance doctrine. It is important to make a distinction between the phenomenon of conditional relevance and conditional probative value, on the one hand, and the legal rules governing that phenomenon, on the other hand.(6) If we wish, we can abolish the legal doctrines now governing conditional relevance and conditional probative value. Try as we might, however, we cannot get rid of the phenomenon of conditional relevance -- or, more broadly speaking, the phenomenon of conditional probative value. Practically every inference from evidence to a fact in issue in litigation - and possibly every such inference -- involves a series of inferences rather than just a single inference; that is, practically every inference from evidence to a factum probandum in a lawsuit involves a chain, or network, of inferences.(7) Hence, the force of any single inference is practically always contingent upon, or affected by, at least one other inference.(8)

Ball himself fully understood that the relevance of a great deal of evidence about a fact in issue -- and possibly of all such evidence -- is in some sense contingent upon inferences about other facts. Ball's own critique of the conditional relevance doctrine rests in part on his thesis that the relevance of practically all evidence is in some sense conditional.(9) Friedman's article, however, exposes a signiticant weakness in Ball's argument. Even if one believes...