BACKGROUND: High rates of mental disorders have been found in detained juvenile offenders, whereas the role of psychopathology in non-detained offenders is less clear. Therefore, the present study compared psychopathology in male non-detained delinquent juveniles and two matched samples from the community and an adolescent psychiatric clinic. METHODS: 125 male adolescents aged 11 to 19 years (m = 16.2 years, SD = 1.5 years) from an outpatient adolescent forensic clinic were compared to a community sample from the Zurich Adolescent Psychology and Psychopathology Study (ZAPPS) and a referred sample from a psychiatric clinic matched for age and nationality. All subjects responded to questionnaires measuring internalizing and externalizing problems, depressive symptoms and self-esteem. RESULTS: The sample of non-detained juvenile offenders showed similar rates of self-reported internalizing and externalizing problems when compared to the community sample, whereas the clinic sample displayed an increased rate of various disturbances. Similar results were found also for self-esteem. In agreement with these findings, non-detained juvenile offenders less frequently had a psychiatric diagnosis after full clinical assessment when compared to the clinical sample. However, a diagnosis of conduct disorders and a lower IQ range was found more frequently in non-detained juvenile offenders. Offenders with serious delinquent acts and involving weapons showed higher depression scores than the rest of the offenders. CONCLUSION: In non-detained assessment situations before court examination, juvenile offenders present rather normal behaviour. Their lack of awareness of potential behavioural problems should be considered during assessment and treatment of this group of offenders.