The identification of potential child maltreatment using reliable and valid screening instruments is of particular importance in high risk populations. The current study investigates the psychometric properties of the Brief Child Abuse Potential (BCAP) Inventory in mothers enrolled in opioid substitution therapy. The BCAP Risk Abuse scale had strong internal reliability. Comparisons between valid and invalid protocols (ae4 on the Lie scale, >1 Random Responding) failed to find systematic differences across most variables although those with a faking good profile had significantly lower scores on psychological well being. A six-factor solution was obtained and was conceptually strong. Subsequent analyses suggested Rigidity may be an independent subscale that needs further investigation. These results add further evidence for the potential utility of the BCAP as a measure of child abuse potential. Replication studies are needed to ascertain whether the subscales derived have convergent and predictive utility.