There is ongoing debate about the methods that evaluators should use to assess the adaptive functioning of an individual in an Atkins claim, including the appropriateness of using self-report measures and extent to which adaptive functioning measures are valid for persons with a history of violent offending. This study examined whether offenders' self-report adaptive functioning scores tended to decrease as their level of psychopathic traits increased. Eighty-five male felony probationers completed the self-report version of the Adaptive Behavior Assessment System – II (ABAS-II: Harrison & Oakland, 2003), the Psychopathic Personality Inventory – Revised (PPI-R: Lilienfeld & Widows, 2005), and a brief intelligence screening measure. ABAS-II composite scores were negatively correlated with PPI-R Self-Centered Impulsivity and Coldheartedness scores, but positively correlated with Fearless Dominance scores. These relationships appeared to be due, in part, to over-reporting symptoms of impairment across measures, suggesting that scores on self-report adaptive functioning measures may be especially susceptible to feigning. Copyright © 2012 John Wiley & Sons, Ltd.