Experts undertook a huge study that discovered depressed people are three times more likely to commit a violent offence than the general population.
The study looked at 47,000 people who were diagnosed with depression in Sweden and compared them with people who were not suffering from the mental illness.
Researchers found that the three-fold risk even remained after allowing for a previous history of violence, socioeconomic background, substance abuse and previous criminality.
Professor Seena Fazel of the university said: “This isn’t something that is talked about. We think the link between depression and violence has been neglected until now. The more symptoms they have the stronger the link becomes.
“The most common crime is assault, but there are sexual assaults and murders.”