Giving psychiatric drugs to ex-prisoners can lead to a huge reduction in re-offending, according to a new study.
The treatment can help make those given to violence more pacified and allow people to adjust more easily to life outside of confinement, according to the research from Sweden.
Rates of violent re-offending plunged when former inmates were treated with medicine, according to the work.
Treatment with antipsychotic drugs saw a 42 per cent fall in the rate of violent re-offending. Treatment with psychostimulants led to a 36 per cent drop and drugs used to help with addictive disorders cut violent assaults by more than half.
The research looked at prisoners from across Sweden who were released between 2005 and 2010, and watched their progress until the end of 2013. The study looked at 22,275 former inmates, and found that 4,031 of them committed violent offenses during the period studied.
Lead researcher Professor Seena Fazel, from Oxford University's Department of Psychiatry, said: "Many countries are keen to reduce the number of people in their prisons, but are unsure how to balance rehabilitation with protecting the public.
"This study raises the possibility that prescribed medications may provide a way to cut the risk of violent re-offending, as part of a wider package of support.
"The research also highlighted that medications seem to work beyond their immediate effects on symptoms.
"We have shown that in a population with many mental health problems and high risks of re-offending, improving adherence and links with community health services may offer an effective way to improve outcomes for the individual prisoner and also public health and safety more broadly."
The findings are published in the Journal of the American Medical Association.
