Moral engagement produces strong emotions that help individuals refrain from serious criminal behavior, but what if a youth is unable to experience these emotions. Based on a sample of adjudicated delinquents and using a series of structural equation models, we test whether moral disengagement varies by level of psychopathy in relation to criminal onset and assess this stability across gender. Psychopathic personality features, moral disengagement, and family stress intermixed in diverse ways depending on the severity of psychopathic personality and gender. At higher levels of psychopathy, the effect of psychopathy on criminal onset was unmediated. However, moral disengagement was found to have mediating effects on criminal onset at lower levels of psychopathy. Study findings lend support to the hypothesis that due to core emotional deficits, youth high on psychopathy are unaffected by the mechanisms of moral disengagement. Results are discussed in light of theories of morality and psychopathy and the treatment of moral deficits among youthful offenders.