When a Battered Victim Kills Their Abuser: The Impact of Child and Expert Testimony on Mock Jurors' Decision-Making

The present study investigated the effects of child and expert witness testimony on mock jurors' decision-making and perceptions of a case in which a female defendant claimed self-defense as the reason for killing her husband during a domestic dispute. A 3 (expert witness: Battered Woman Syndrome [BWS] vs. Social Agency [SA] vs. No Expert) × 3 (child witness: Age 5 vs. Age 8 vs. no child) between-subject design was used to examine the effects of two different forms of expert testimony and their interaction with the presence of a child witness. Jury-eligible participants (N = 370) were recruited from Amazon Mechanical Turk and a Psychology Undergraduate Student Pool. The mock jurors who were exposed to the BWS expert perceived the defendant as more guilty when an 8-year-old testified compared to when no child testified at all. Furthermore, when the jurors were exposed to the BWS expert, they imposed a harsher sentence on the defendant when an 8-year-old child testified compared to a 5-year-old child or no child testifying. Although the jurors perceived the defendant in the BWS condition as more fearful compared to no expert and the SA condition, this knowledge did not seem to translate into a lighter verdict or sentencing decision. This study aims to provide guidelines for future researchers and legal professionals considering the issue of expert testimony and child witnesses in intimate partner homicides.