Major mental illness and violence history as predictors of institutional misconduct and recidivism: Main and interaction effects.

Abstract

The purpose of this study was to ascertain whether major mental illness (MMI) and violence history (VH) interact in their effect on institutional misconduct and recidivism. MMI and VH were measured in two overlapping groups of male medium security federal prisoners and correlated with institutional misconduct and recidivism. Age and the main effect of MMI were significant predictors of general and aggressive infractions in 2,627 male prison inmates before the MMI × VH interaction term was entered into a Cox regression equation. Once the interaction term was entered into the equation, the MMI × VH interaction predicted relative hazard (risk) but neither main effect (MMI, VH) was significant. There was no interaction effect, however, when age, prior substance abuse, MMI, VH, and the MMI × VH interaction were used to predict general and aggressive recidivism in a group of 1,163 male inmates previously released from custody. Age and the VH main effect achieved significance in both recidivism analyses whereas the MMI main effect failed to achieve significance in either analysis. Whereas major mental illness was not a risk factor for future antisocial behavior in current and former prison inmates, when paired with a history of violence it predicted increased risk of general and aggressive institutional misconduct. Violence history, on the other hand, was a consistent predictor of recidivism. These results indicate that it may be advisable to review both mental health and violence history when screening inmates as a prelude to managing concomitant MMI and violence propensity.