E\u27 Is for Eclectic: Multiple Perspectives on Evidence (Symposium: New Perspectives on Evidence)

A conference titled New Perspectives on Evidence: Experts, Empirical Study and Economics has a pronounced alliterative theme, a theme made even more apparent when, inevitably in evidentiary discourse, epistemological questions come to the fore. It is enough to make one suspect that the conference is secretly brought to you by the letter E, hiding behind its public front, the Olin Foundation. Putting aside such conspiratorial thoughts, all these E\u27s suggest the presence of a meta- E -Eclecticism. Indeed, I believe this conference has demonstrated the need for an eclectic approach to evidentiary problems. That should be no surprise. The domain of evidentiary law and discourse is determined not by a given intellectual approach butto the extent it is determined at all-by a set of problems, central among which is the question of what kinds of information ought to be presented to an adjudicative factfinder. One trying to provide sensible, useful analysis of an evidentiary problem acts at her peril if she ignores any available source of wisdom and guidance. One consequence of eclecticism is that we do not have to worry about boundaries very much at all. Does a particular line of reasoning qualify as economic?1 It does not particularly matter; however the line may be characterized, if the reasoning advances analysis, that is all to the good. For expository convenience, though, I will discuss separately three E -perspectives that are important in this symposium: empiricism, economics, and epistemology. Eclecticism means that multiple perspectives on evidentiary problems may have something to offer. The other side of that coin is that no given perspective is a panacea; each one leaves work for others to do. I will discuss the value and limitations of each of these three perspectives. I will then focus on one particular E -problem that has been addressed in this symposium, that of expert evidence. I will suggest how each of these approaches-I do not mean to exclude others-can assist analysis and understanding of expert evidence, and I will focus on the core issue of the standard for admitting such evidence. One substantive theme will run throughout many of my comments. I believe the proposition that some evidence must be excluded because the jury is likely to overvalue it has been given far too much credence in evidentiary discourse.2 Exclusion is not justified on the basis of overvaluation unless the jury so massively overvalues the evidence that considering the evidence leads it further away from, rather than closer to, the truth. In fact, the empirical evidence does not support the proposition that overvaluation is a significant phenomenon. I think we should try to construct evidence law without relying on an overvaluation rationale. In some situations, exclusionary rules may be justified on other grounds, such as the vindication of deep underlying values or the prospect that the evidence would bias the jury against a party (a factor altogether different from overvaluation).3 In other situations, exclusion is simply unjustified