Gender of an Expert Witness and the Jury Verdict
Couch, James V., Sigler, Jennifer N., The Psychological Record
Articles discussing the admissibility of expert witness testimony have appeared more frequently as the courts and professionals grapple with the standard to be used for admitting expert testimony (Blau, 1998; Landsman, 1995; Ogloff, 1999; for example). Unlike evidentiary witnesses called to testify at a trial, the expert witness can not only testify to specific facts but also express an opinion about those facts.
Because the influence of an expert can be extremely important to the outcome of a legal proceeding, it is reasonable to ask what variables modulate the impact of the testimony on the jury's decision. Besides variables such as credibility, credentials, manner of presentation, and so forth (Bank & Poythress, 1982), the gender of an expert witness has been implicated as a possible modulator of the effectiveness of testimony. Schuller and Cripps (1998) studied the effect of expert witness gender on a mock juror's individual verdict in a homicide trial in which the battered women syndrome was used as a defense. Results indicated that a female expert witness was more effective in presenting evidence for the battered women syndrome than a male expert. Swenson, Nash, and Roos (1984) used a simulated child custody dispute to examine the influence of the expert's gender. In this investigation, the expert was portrayed as a male or female neighbor, psychiatrist, psychologist, or social worker. Swenson et al. reported a small but statistically significant difference with the female expert being perceived as more likely to provide an expert opinion.
Memon and Shuman (1998) examined the influence of the gender and race of an expert witness in a medical malpractice case and reported no difference because of the gender of the expert. This result is similar to that reported by Vondergeest, Honts, and Devitt (1993) who varied the gender of an expert testifying as a polygraph examiner and reported no significant differences in the verdicts of how the expert was evaluated by the mock jurors.
Based upon these investigations, what can be said about the influence of an expert's gender on the outcome of trials? In the two studies where a significant difference was reported in favor of the female expert being more persuasive (Schuller & Cripps, 1998, Swenson et al., 1984), the situation before the court was one where a female might be perceived as having more expertise than a male. If this is the case, then it might be reasoned that jurors evaluate the evidence of an expert not from an absolute standpoint but rather in terms of the context of the case. Thus an expert's efficacy might be modulated by the preexisting expectations of the jurors hearing the evidence. In other words, if the expert witness is perceived to have some special insight into the area about which they are testifying (e.g., a female testifying about the battered woman syndrome), then the testimony is attributed more weight than the testimony of an expert without such insight.
Further support for this position comes from a literature review, Shuman, Champagne, and Whitaker (1996) concluded that the "typical juror forms impressions of experts stereotypically, based on the occupation of the experts, and superficially, based on the personal characteristics of the experts" (p. 382). If the occupation of an expert is an important determinant of the efficacy of expert testimony, what might be a juror's impression of an expert's testimony, if an expert's occupation is incongruent with a juror's expectation of the gender of the expert's occupation? That is, if a juror's interpretation of the expert's testimony is not absolute but rather modulated by the context (type of case being considered, etc.) then an expert having an occupation that is not congruent with the juror's expectation for that occupation may not be as effective in establishing his or her case as an expert having an occupation that is congruent with the juror's expectation. …