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In this video, Columbia University forensic psychiatrist Michael Stone dispels common myths about the intersection of violent acts and mental health disorders. He addresses the question of whether people with schizophrenia are more likely to commit violent crimes and how much danger they present to society at large. The answer? Not as much as you’d imagine, given the sensationalism of mainstream media coverage.

Michael Stone: The general public, I think, is at the mercy of what they read in the papers. And some of the crimes committed by mentally ill people are very dramatic and unusual. For instance some years ago — it must be maybe more than 20 years ago — there was a fellow Juan Gonzalez on the Staten Island ferry that took a sword of some sort and killed two people. And that of course was very dramatic and it was very much publicized. So it’s things of that sort that the public, not knowing the full statistical picture, are going to get the impression: Oh my god, mentally ill people, you really better steer clear of them if you knew who they were because they’re highly at risk to do something terrible and dramatic and violent.

So it gives the public the worry, the oh my god, the people who are mentally ill are doing these things all the time and the people that do them must be mentally ill because it’s crazy to commit murder. But the fact of the matter is from a standpoint of actual, diagnosable psychosis by a qualified psychiatrist, the number of violent crimes that are committed by mentally ill or psychotic people is relatively small, maybe 5 or 6 or 7 percent. If you’re schizophrenic, the risk of your doing a violent crime is four to six times higher than it would be in the general population. That means that 94 or 96 percent of people who are diagnosed schizophrenic are not committing a violent crime.

However, within the group who are — just to focus for the moment on schizophrenia — who commit a violent crime it depends on a number of other variables. For example if the person is alcoholic, has abused alcohol, then the rate goes up; maybe the risk is like 30 percent or 38 percent risk in the next year they’re going to do something violent. Oftentimes when a violent crime is committed by somebody who seems to be mentally ill, the police have a sense that this guy is not operating with a full deck, as it were. They have their own little expressions about that. They will have the person incarcerated. Maybe in New York City, it could be at Ryker’s or wherever in some local jail. And then have him evaluated by two psychiatrists or two psychologists who are able to do an adequate evaluation of the person’s mental state. If those two people conclude the person is — we don’t say insane. We say not guilty by reason of mental disease or defect — then they will be relegated to a forensic hospital rather than a prison. The exception would be if the crime itself is such high profile that the citizenry would be outraged at the idea of the person being put in this soft berth of the hospital such as Andrea Yates who drowned her five children. She was grossly psychotic. She was hallucinating; she was way out. But the nature of the crime was such that, especially in Texas, that she did get a break. She went to the prison.

Now there was a second trial and there she ended up finally where she should have been in the first place, in a forensic hospital. What the public doesn’t know is a lot of times a person in a forensic hospital was going to be incarcerated there and admittedly a more soft environment than a prison, but for way longer than the person would have been if he had gone through the ordinary prison system. In other words if you rape somebody and it’s a first rape and you’re young you go to prison, we’ll give him 10 years with three off for good behavior. Whereas if a person did a rape of a violent sort and was psychotic at the time and adjudicated as mentally ill and so on, he will go to a forensic setting. And perhaps be kept there for many, many years because it may be a violent record that preceded the major violent episode so that the person’s considered a pretty dangerous person until they’re much older.

And so that the public is actually often in a safer situation with a person in a forensic setting whenever they come up for their two-year evaluations — is the person okay to be released now? The psychiatrist says, "Nope, he’s not ready yet." And I’ve seen serial killers, for example in the forensic setting, who are kept for life. Whereas the same person having killed one or two people when they couldn’t prove that the person had also killed some other people besides would have gotten a comparatively light sentence in a prison, but ended up, justly so, separated from society forever in a forensic hospital. And they’re the ones that often they — let’s say the families are very worried about and the family will get them in the car and say we’re taking you to a picnic, but actually they take them to the emergency room because if the person knew that they were being taken to a psychiatric emergency room, they would not agree to go. And so then they feel railroaded, right arm twisted into going to the psychiatric emergency room or whatever by the family. But the reason that the family felt they had to do that was because maybe the person was behaving peculiarly or even being very disruptive or even maybe doing some assaultive or violent things at home. And they had no choice but to try to get this person into a situation of help even if they had to do it by trickery, kind of benign trickery.