Date Submitted
6-2025
Faculty Advisor
Jason Malousek
Abstract
A not guilty by reason of insanity (NGRI) plea is a legal defense in which the defendant admits to the allegations against them, while asserting they should not be held criminally liable due to the role of a mental illness at the time of the offense. Ultimately, either a judge or a panel of jury members determine whether that plea is substantiated by a preponderance of the evidence. Although jurors are instructed to consider only the evidence presented during a trial, much of the literature on the subject demonstrates an abundance of extraneous variables that can influence individual juror decision-making. Albracht & Behnken (2019) established a significant relationship between mock juror experience with mental illness and perception of defendant culpability. That is, participants serving as simulated jury members in a research study who have a mental disorder are more inclined toward a particular verdict. To build upon these findings, the current study aimed to identify whether the diagnostic category of a mock juror's psychiatric diagnosis is predictive of returning a particular verdict (i.e., NGRI, guilty). Researchers hypothesized that mock jurors diagnosed with a trauma and stressor-related, schizophrenia-spectrum, and neurodevelopmental disorders would find the defendant NGRI at a higher rate than individuals with no psychiatric diagnosis. Ultimately, a lack of participants endorsing schizophrenia-spectrum disorders resulted in their removal from analysis. Utilizing a logistic regression, statistical analysis led to the rejection of the hypothesis; however, exploratory analysis revealed statistically significant results between the endorsement of anxiety and depressive disorders and NGRI verdicts.
