IntroductionTo our knowledge, a limited number of studies address criminality among psychiatric patients as depicted in legal files.ObjectivesThe objective of the present study was to provide demographic, psychiatric, legal/criminal data about psychiatric patients in Greece.MethodsLegal case files of 100 adult subjects, 90 male/10 female, 88 Greeks/12 foreigners were reviewed.ResultsSeventy eight percent of the subjects had at least one psychiatric evaluation prior to the commitment of the crime. The main diagnoses at the time of the criminal act were: schizophrenia spectrum psychosis (18%), anti-social/borderline/mixed personality disorder (15%), substance use disorder (15%), alcohol use disorder (10%), depressive affective disorder (6%), mixed anxiety/depressive disorder (6%), bipolar disorder (5%), anti-social personality disorder/substance use disorder (5%), schizophrenia/substance use disorder (3%). In 11% the diagnosis was unknown. Eighty four percent of the crimes committed were homicides/attempted homicides, 6% assaults/(attempted) homicides, 3% property crimes/(attempted) homicides and below 3% assaults, property crimes, sexual offences, drug crimes. The weapon used was a knife/sharp object (42%) or a gun (40%). Perpetrator and victim were strangers in 25% of the cases, just acquaintances in 14%, had a professional relationship in 7%, their relationship was conjugal (15%), they were partners (13%) or relatives (7%). In persons with schizophrenia spectrum psychosis the victims were relatives/spouses in 41.2%, while in other diagnoses the respective percentage was 21.5% (P = 0.044).ConclusionsIn accordance to the international literature, there is a vast need for further research in order to improve forensic psychiatric services and prevent criminality among psychiatric patients.Disclosure of interestThe authors have not supplied their declaration of competing interest.