Efficacy of legal judgments for defendants with traumatic brain injury

Literature has compared the frequency of aggressive behaviors of the TBI population and the non-TBI population, suggesting that the TBI population is predisposed to aggressive tendencies because the injury enables impulsivity, loss of self-control, and the inability to modify behaviors. These behavior changes have consequently, been found to lead to criminal involvement. In fact, the majority of the prison population has sustained at least one TBI in their lifetime compared to the prevalence of brain injuries in the general population. However, there is little research investigating the perceptions of criminality and guilt of these individuals.

Two experiments were conducted that investigated the perceptions of morality, level of guilt, and appropriate sentencing of crimes committed by defendants with different severities of TBI (i.e., mild, severe, and no TBI). Participants were asked to read scenarios about crimes being committed by the defendant. Experiment 1 used a 1-between (crime), 1-within (TBI) mixed design ANOVA testing three dependent variables (morality, guilt, and sentencing). Using a more in vivo jury approach, Experiment 2 used a 3 (TBI)×2 (crime) independent groups factorial design testing the three dependent measures.

Overall, defendants with TBI were found less guilty of their crime, perceived as behaving morally to the crime, and receiving a milder punishment relative to the no-TBI defendants.

In the courtroom, the defense attorney should educate the judge and/or the jury on the effects brain injuries have on the cognition, behavior, and emotions of an individual. Thus, this education will ensure the best verdict is being reached.