NCJ Number
226651
Journal
JOURNAL OF FORENSIC PSYCHOLOGY Volume: 9 Issue: 1 Dated: January-March 2009 Pages: 35-56
Date Published
March 2009
Length
22 pages
Annotation
This study compared experimental conditions utilizing three types of third-party information (TPI) that supported or countered a psychologist’s opinion regarding insanity for differential effects in a mock jury decisionmaking case.
Abstract
Third-party evidence or third-part information (TPI) was found to play a significant role for decisions by the participants, especially when that source of information contradicted their initial decision of agreeing or disagreeing with the psychologist’s opinion. There are a number of decisions that jurors must make when deciding cases that involve psychological experts’ opinions along with TPI. Jurors must decide whether they agree with the mental health expert’s conclusion. Then, they must determine whether there is additional information from other sources specific to the question of the defendant’s mental state that they must take into account. The TPI must be considered in light of the expert’s testimony to determine whether it appears to support or contradict the expert’s opinion. This study investigated these aspects of juror decisionmaking utilizing sequential decisionmaking to understand the jurors’ opinions at points in time when they were cognizant only of the expert’s information and then after they received TPI. The study represents an early attempt to quantify and explore an aspect of forensic evidence and evaluation that has seldom been subjected to anything but anecdotal considerations. Figure, tables, and references