Antisocial personality disorder (APD) and psychopathy have been extensively researched in relationship to criminal behavior and aggression. Comparatively few studies have evaluated these clinical constructs for subtypes of aggression, specifically reactive and instrumental aggression. Moreover, published studies tend to focus on extremes, either prisoners in maximum-security facilities or college samples. The current study utilized jail detainees on a minimum-security unit to retrospectively examine their self-reported reactive and instrumental aggression. Because conduct disorder (CD) is required for APD, the combined APD-CD symptomatology was used to predict subtypes of aggression. As a comparative analysis, facet scores on the Psychopathy Checklist-Revised were also used as predictors. Results of the current study have implications for forensic practice by utilizing aggression as a multi-dimensional construct in conjunction with personality traits (e.g., facets of psychopathy) in risk assessments.