Personality Dimensions Involved in the Adaptation to the Prison Environment: Evidence from Romanian Violent Offenders

Background: Personality traits, particularly those belonging to the Dark Triad (Machiavellianism, narcissism, and psychopathy), may influence violent behavior and adaptation to the prison environment. Methods: The study included 250 male inmates from Bucharest-Jilava Penitentiary, aged between 20 and 67 years. The Emotional Stability Scale (IPIP), the Buss–Perry Aggression Questionnaire, and the Short Dark Triad Scale (SD3) were administered. Statistical analyses included Pearson correlations, multiple linear regressions, and binary logistic regressions. Results: Emotional stability was negatively correlated with aggression (r = −0.48, p < 0.01). Psychopathy significantly predicted physical aggression (t = 11.96, p < 0.001) and anger (t = 9.53, p < 0.001), whereas Machiavellianism predicted verbal aggression (t = 3.14, p = 0.002) and hostility (t = 4.73, p < 0.001). Higher levels of physical aggression were associated with a lower likelihood of participation in educational activities (Exp(B) = 0.93, p = 0.032). Conclusions: The influence of Dark Triad traits on aggression is differentiated, with psychopathy exerting the strongest effect. Low emotional stability increases vulnerability to hostile behaviors. These findings support the need for multidimensional psychological assessments and tailored intervention programs designed to enhance violent offenders’ engagement in educational activities aimed at impulse control and empathy development within the prison environment.