People with bipolar disorder who abuse substances are no more likely to commit violent crimes than substance users who do not have bipolar disorder, according to a study reported by the BBC.

A pervasive stereotype in society is that of the crazed person who goes on a violent criminal rampage. But is there any truth to this archetype? That is what Seena Fazel, MD, and her colleagues from Oxford University in Oxford, England, hoped to find out. They examined data of 3,700 people in Sweden who had been diagnosed with bipolar disorder along with 4,000 of those individuals’ siblings and 37,000 people in the general public.

The researchers found that people with bipolar disorder were no more likely to commit a violent crime. Rather, alcohol and drugs abuse was the most potent predictor of violent crime. In fact, substances abusers, whether or not they had bipolar disorder, were about six to seven times more likely to commit a violent crime than people who did not have a substance abuse problem.

“It’s probably more dangerous walking outside a pub on a late night than walking outside a hospital where patients have been released,” Fazel told the BBC.

A previous study by the same authors regarding people with schizophrenia found similar conclusions.