AUDIE CORNISH, HOST:
An inevitable question today, why would someone commit a mass shooting? And who would kill children in a school? Jack Levin has studied those questions for years. He's a sociologist and criminologist at Northeastern University in Boston and he joins us now. Welcome, Jack.
JACK LEVIN: Thank you.
CORNISH: Now, is there a psychological profile of a mass shooter, some qualities that seem to link the people who commit these kinds of crimes?
LEVIN: You know, most mass killers have suffered some kind of chronic depression and frustration. Over a long period of time, they externalize responsibility, blaming everybody but themselves for their failings. They have some kind of an acute strain, a catastrophic loss - the loss of a job, the loss of a relationship at home, maybe even a terminal illness.
And they have the means whereby they can do a lot of damage. They have training in and access to firearms, for examples, which means that the body count may be very large.
CORNISH: Is it clear that there is any actual psychosis involved?
LEVIN: You know, there are cases of psychosis, especially schizophrenia, but only in those public massacres that happen, for example, in a cinema, in a shopping mall, where the victims are indiscriminately targeted. There, all humanity is involved and the killer believes that everybody's against him. That often is a reflection of his terrible mental health.
But when it comes to most mass killings, psychosis is not an issue. There may be personality problems involved. But for the most part, the pathology is situational, something just horrendous happens, catastrophic, as viewed by the killer, and he decides to get even. He seeks sweet revenge against everybody he feels implicated in his miseries.
CORNISH: At the same time, people tend to think that mass killers, quote, unquote, "snap" but then you learn more about them and find out there's been build-up to the crimes, preparation.
LEVIN: Very few mass killers, including school shooters, actually snap. They don't go berserk. They don't run amok. They don't go bonkers. We have so many ways of saying that. But the truth is that most of them are methodical. They plan this sometimes for months. They'll get the weapons and the ammunition. At Columbine, for example, the planning took 13 months. And that's not unusual.
CORNISH: So, even if researchers were able to truly develop some sort of profile, how helpful would it be in preventing future mass shootings, mass killings, if these crimes remain so hard to predict?
LEVIN: That's a great point, and sadly enough, we simply can't predict, and here's the reason. The issue is one of false positives. There are many individuals who have all the symptoms but they never get the disease. They fit the profile to a T. But so do millions of other people who don't hurt anyone. The profile has limited utility with respect to prediction.
It can explain why a killer does that, and after the fact we all become psychologists and recognize every warning sign, every red flag. Unfortunately, beforehand, we don't.
CORNISH: Now looking back over the last two years, there have been what seems like so many recent mass shootings: Tucson in 2011; there was Aurora, Colorado; and the Sikh temple in Wisconsin this year. Are people right to believe that this kind of violence is increasing?
LEVIN: Not really. I know it looks that way, and there have been some tragically large body counts, which accounts for a lot of the publicity. There have been a few more public massacres, random massacres, and they also get people very anxious because everybody goes to the cinema, and everybody's in school. So, you know, it makes people nervous that they might be victimized.
But the truth is that there's still about 20 mass killings every year in this country, and that has been true for decades. There are about 100 to 150 victims of mass murder. Now that sounds terrible, and it is. It's tragic. But keep in mind that that number pales against the some 15,000 single-victim homicides in this country on an annual basis, and that's really where the problem lies.
CORNISH: Jack Levin, he is co-director of the Brudnick Center on Violence at Northeastern University in Boston. Jack Levin, thank you for speaking with me.
LEVIN: Thank you.
ROBERT SIEGEL, HOST:
We'll follow this story throughout today's program. Details are still scarce, but here is a recap of what we do know at this point. In Newtown, Connecticut, just after 9:30 this morning, a 911 call was made regarding Sandy Hook Elementary School. A shooter apparently had entered the school and fired on students and adults in two rooms, both in the same area of the school.
CORNISH: State police say 18 children were found dead at the scene. Two more were pronounced dead at the hospital. And six adults were killed at the school, including the mother of the shooter. [POST-BROADCAST CORRECTION: The mother of the shooter was not one of the six adults killed at the school.]
In total, 26 victims at Sandy Hook Elementary. The shooter is dead as well, but state police are not yet identifying the suspect or the suspect's cause of death.
SIEGEL: There is one more adult dead in Newtown, Connecticut, described as an individual the perpetrator lived with. Connecticut state police say their investigation is ongoing and there are still a lot of details that they cannot confirm or discuss.
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