The aim of the present study was to determine the prevalence of mental disorder among male prisoners in Greece and to examine possible association between psychiatric disorders and the criminal history of the subjects. A randomly selected sample of 495 convicted prisoners was investigated, with structured psychiatric instruments. Psychiatric disorder was diagnosed in 45.06% of the sample. The main diagnoses were personality disorder 15.96%, substance misuse 14.54%, depression 4.44%, neurosis 3.64% and psychosis 2.63%.

Offenders were also classified according to the type of offense with which they were charged, in three major crime categories: non-violent, violent, and drug related crimes. Non-violent crimes represented 40.7% of all investigated criminal records, followed by drug related crimes 30.3%, and violent crimes 28.0%. Concerning the association between psychiatric diagnosis and criminal records personality disorders was significantly related to violent crimes p<0.05. There was also significant relation between substance misuse and drug related crimes p<0.05. Depression was also correlated to drug related crimes p<0.05. No other mental disorder related significantly to any crime category investigated.