I was struck by footnote 17 of Justice Souter’s opinion in the Exxon case issued today:

The Court is aware of a body of literature running parallel to anecdotal reports, examining the predictability of punitive awards by conducting numerous “mock juries,” where different “jurors” are confronted with the same hypothetical case. See, e.g., C. Sunstein, R. Hastie, J. Payne, D. Schkade, W. Viscusi, Punitive Damages: How Juries Decide (2002); Schkade, Sunstein, & Kahneman, Deliberating About Dollars: The Severity Shift, 100 Colum. L. Rev. 1139 2000); Hastie, Schkade, & Payne, Juror Judgments in Civil Cases: Effects of Plaintiff’s Requests and Plaintiff’s Identity in Punitive Damage Awards, 23 Law & Hum. Behav. 445 (1999); Sunstein, Kahneman, & Schkade, Assessing Punitive Damages (with Notes on Cognition and Valuation in Law), 107 Yale L. J. 2071 (1998). Because this research was funded in part by Exxon, we decline to rely on it.

(my emphasis)
Now I used to keep up with the psychological literature more than I do now, but I remain somewhat familiar with this work and very familiar with the work of some of the authors cited above. It is really top notch work. So i find this footnote troubling. There will be cases (including election law cases) in which there are no extant studies on an empirical question at the heart of a case. At that point, it makes sense for litigants to fund such research. Indeed, when such research appears in an expert report subject to cross-examination, I assume the Court has no problem relying upon the evidence. So why should it be different when a litigant funds the research, particularly if the research has gone through peer review and of course if the funding source is disclosed so that the opposing side may probe for bias?
UPDATE: Dave Hoffman blogs about the same footnote, pointing out criticisms he and others have made of these particular studies. I can’t quarrel with that—as I said, I haven’t followed this area closely recently. But I stand by my general point, that a categorical rule as stating by Justice Souter–that litigant-funded research, whether or not peer-reviewed or published—should not be considered by the Court in its rulings. Others have pointed out to me that some of the studies cited in the footnote were not peer reviewed. But again, that doesn’t figure into the Court’s categorical and unfortunate rule.