http://goo.gl/RNUXHM
According to the patients, substance abuse and social destitution were important background factors to the crimes. This is consistent with epidemiological studies of the relationship between violence and mental illnesses. The relationship which can initially be seen in these studies disappears if you take into account factors such as alcohol and social circumstances.
"Extremely few of the people who are mentally ill commit crimes. The connection between alcohol and violence is on the other hand clear, which means that anyone who wants to be safe should first and foremost beware of alcohol and not those who are mentally ill", says Pontus Höglund.
Having difficulty controlling one's actions and finding alternative measures was present in many of the patients' stories, regardless of their psychiatric diagnosis. Yet it is mainly the diagnoses that determine whether a person who committed a crime is considered to have done so because of a "severe mental disorder" and is to receive forensic psychiatric care rather than prison.