Abstract: Recent literature has suggested that current methods of diagnosing adolescents with conduct problems do not allow for a meaningful differentiation between those youth who are more likely to persist in chronic offense patterns and those who will desist. Researchers have proposed that utilizing psychopathy as an alternative classification will more effectively differentiate among juvenile offenders. Previous research with youth has demonstrated that psychopathy scores predict important variables assessing criminal behavior. Fewer studies have addressed the construct validity of psychopathy scores. This is an important step in clarifying how well the construct of psychopathy generalizes to youth. The current study examined the relationships among psychopathic traits in adolescent males and core features of psychopathy. Specifically, the relationships among psychopathic traits (measured by PCL:YV and YPI scores), narcissism (measured by NPIC scores), proactive violence (scored from file reviews), trait anxiety (measured RCMAS scores) and fearlessness (measured by TAS scores) were explored in a population of 60 incarcerated males between the ages of 14 and 18, convicted of a violent crime or cited for an institutional case of violence, and recruited from juvenile detention facilities. Relationships among these variables were examined and predicted to mirror findings established in the adult literature. The participants were predominantly Latino (60%), which provided an additional opportunity to explore the application of psychopathy to racial groups that have been underrepresented in previous research. There was mixed support for the applicability of the construct of psychopathy in youth. PCL: YV factor 1 scores (assessing callous/unemotional traits) were positively related to both institutional proactive violence and narcissism scores, providing some support for the construct validity of psychopathy scores. However, measures of trait anxiety and fearlessness were unrelated to PCL:YV factor 1 and 2 scores or to self-reported psychopathic traits, so relationships identified in adults were not consistently found in the current sample. However, PCL:YV factor 2 scores were positively associated with trait anxiety scores in Latinos. The absence of significant findings between psychopathic traits, trait anxiety and fearlessness in the current study could point to legitimate developmental differences in how psychopathic traits operate in youth when compared to adults, to the need to study different ethnic groups individually, or to limitations in the measures chosen to assess fearlessness in this study.