Date of Award


Document Type


Degree Name

Master of Arts (MA)



First Advisor

Dr. Ray Millimet

Second Advisor

Dr. Nancy Perry


This study examined the influence of expert witness testimony and jury instructions on mock jurors' final verdicts of guilt in a case where the sole eyewitness to a murder/abduction was a five-year-old-child. One hundred and ninety-two college students heard an audio-taped trial proceeding in which the testimony of an expert witness and the jury instructions were varied (both supporting or discrediting of a child witness' testimony or mixed testimonies). Individual judgments of guilt and judgments after group deliberation were recorded. It was hypothesized that expert witness testimony and jury instructions would significantly influence verdicts. Contrary to predictions, neither expert witness testimony nor judge's jury instructions influenced individual ratings of guilt, group directions, or time spent in deliberation. It was found that when a supporting expert witness was paired with a supporting judge the individual guilty rates were higher than when a supporting expert witness was paired with a discrediting judge. Only 37% of the groups reached a mutual decision, with groups who heard congruent supportive messages significantly less likely to reach a mutual decision than those groups who heard congruent discrediting messages. These letter groups were significantly more likely to reach a mutual decision. Implications for future research are discussed.


A Thesis Presented to the Department of Psychology and the Faculty of the Graduate College University of Nebraska In Partial Fulfillment of the Requirements for the Degree Master of Arts University of Nebraska at Omaha. Copyright Debra Schwiesow November, 1989