Mentally disordered patients that abuse drugs or alcohol have a larger number of criminal convictions. Early starters who had their first conviction before the age of 18, especially, more often have a diagnosis of substance abuse and are more often intoxicated at the time of the offense compared to late starters. The present study involved four groups of Dutch patients (n=137): three groups of violent offenders (psychotic and personality disordered patients) and one group of non-delinquent psychotic patients from general psychiatry. All data were retrieved retrospectively. The results showed that early starters were intoxicated more often, started with substance abuse at an earlier age and more often had a diagnosis of substance abuse at the time of the index offense than late starters. Personality disordered offenders were intoxicated more often and more often had a prior diagnosis of substance abuse at the time of the offense than psychotic offenders. To a limited extent, psychotic offenders with a diagnosis of a substance-related disorder or intoxication at the time of the offense had a more extensive criminal history than personality disordered offenders. Substance abuse has an aggravating effect on criminogenic behavior, depending on the age at first conviction and diagnosis.