Trial Practice, Ethics, Theory: Lawyers Judging Experts

David S. Caudill, “Lawyers Judging Experts: Oversimplifying Science and Undervaluing Advocacy to Construct an Ethical Duty” (2011) 38 Pepperdine Law Review 674


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The fact that judges, typically untrained in science, need to “resolve disputes among respected, well-credentialed scientists about matters squarely within their expertise,” a “daunting task,” seems to suggest that lawyers could too. But judges do not always agree on the admissibility of expertise, and discerning reliability has proved to be controversial. To expect attorneys—and this is what the proponents of a duty to vet experts expect—to do sufficient scientific research to create their own reliability controversy, make a determination as to the ultimate reliability of their own experts, and face ethical sanctions if they err is going too far. While it is easy to choose examples that support a compelling argument for a responsibility to vet experts, the complexity of the scientific enterprise, in terms of its diverse methodologies, probabilistic conclusions, and genuine scientific disagreements, counsels against a broad, new ethical duty. Indeed, some of the arguments for that new duty seem to rest on unrealistic assumptions about science and the ease with which reliability determinations can be made. Moreover, a broad duty to vet experts would represent a serious and problematic departure from the lawyer’s role as an advocate. “ (676-677)


The real problem with the proposed duty to vet expertise is the proposition that attorneys should come to a good faith belief in validity. What if I am uncertain, that is, I am not really sure if my expert physician’s opinion or the other side’s epidemiologic evidence is correct? Is that uncertainty a failure to come to a good faith belief in validity or a justifiable uncertainty arising out of a scientific controversy? One could tell me to go back to the literature to settle the controversy. But the attorney’s role as an advocate, notwithstanding its limitations in terms of duties of candor to the court, should remain particularly distinct from the judge’s and jury’s role in resolving such disputes. When Saks said that it “is hard to think of principled reasons why an attorney should not be obligated to acquire a good faith basis for believing” that proffered expertise is valid, the reasons that he missed were the complexity of a lot of courtroom expertise and the advocate’s traditional role in our adversary system. (707-08)

( Footnotes omitted in each except)

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