Competition in the Courtroom: When Does Expert Testimony Improve Jurors' Decisions?

43 Pages Posted: 16 Apr 2008 Last revised: 21 Feb 2009

See all articles by Cheryl Boudreau

Cheryl Boudreau

University of California, Davis

Mathew D. McCubbins

Department of Political Science and Law School, Duke University (deceased)

Date Written: February 14, 2009

Abstract

Many scholars lament the increasing complexity of jury trials and question whether the testimony of competing experts helps unsophisticated jurors to make informed decisions. In this paper, we analyze experimentally the effects that the testimony of competing experts has on 1) sophisticated versus unsophisticated subjects' decisions and 2) subjects' decisions on difficult versus easy problems. Our results demonstrate that competing expert testimony, by itself, does not help unsophisticated subjects to behave as though they are sophisticated, nor does it help subjects make comparable decisions on difficult and easy problems. When we impose additional institutions (such as penalties for lying or a threat of verification) upon the competing experts, we observe such dramatic improvements in unsophisticated subjects' decisions that the gap between their decisions and those of sophisticated subjects closes. We find similar results when the competing experts exchange reasons for why their statements may be correct. However, these additional institutions and the experts' exchange of reasons are much less effective at closing the gap between subjects' decisions on difficult versus easy problems.

Keywords: institution, expert, testimony, competition, jury, sophistication, adversarial, legal, trust

JEL Classification: C90, C91, D70, D80, D81, D83, K10, K41, K40

Suggested Citation

Boudreau, Cheryl and McCubbins, Mathew D., Competition in the Courtroom: When Does Expert Testimony Improve Jurors' Decisions? (February 14, 2009). 3rd Annual Conference on Empirical Legal Studies Papers, Available at SSRN: https://ssrn.com/abstract=1121025 or http://dx.doi.org/10.2139/ssrn.1121025

Cheryl Boudreau (Contact Author)

University of California, Davis ( email )

One Shields Avenue
Apt 153
Davis, CA 95616
United States

Mathew D. McCubbins

Department of Political Science and Law School, Duke University (deceased)