In the wake of the horrific mass shooting in Newtown, Connecticut, can science offer a better way to predict violent behavior and prevent such a tragedy? With leading experts in psychiatry and psychology such as Columbia's Paul Appelbaum and Harvard's Steven Pinker, NOVA investigates what we know and don't know about the roots of violent crime. In a critical assessment that cuts through the speculation that has surrounded much television coverage of the Newtown tragedy, NOVA's experts assess the hard reality of current violence prediction and the hope of future prevention.
Can Science Predict Mass Murder?
PBS Airdate: December 21, 2012
POLICE DISPATCHER: The caller is indicating she thinks someone is shooting inside the building.
NEWS VOICE (ABC News/Film Clip): State and local police are on the scene.
NARRATOR: News breaks of a horrific shooting in Newtown, Connecticut.
BRIAN ROSS (ABC News/Film Clip): Police identified the shooter as 20-year-old Adam Lanza.
NARRATOR: Everyone is asking the same questions.
BRIAN ROSS (ABC News/Film Clip): …why that young man was set off.
NEWS VOICE (ABC News/Film Clip): Why the attack of the children at the school.
NEWS VOICE (CBS This Morning/Film Clip): Are there warning signs for people like this.
NARRATOR: Understandably, the first place everyone looks for answers is inside the mind of the killer.
NEWS VOICE (Film Clip): In our wildest dreams, we can't find any logical reasoning.
NARRATOR: What was going on inside Adam Lanza's brain.
NEWS VOICE (ABC News/Film Clip): A relative told ABC News today that Adam was obviously not well.
NEWS VOICE (FOX47 News/Film Clip): …experts saying today that the problem lies partly with issues of mental health.
NARRATOR: But what do we really know.
JOSHUA W. BUCKHOLTZ (Harvard University): One of the most infuriating things, as a scientist and as a person, that I see on television and on other media, right now, is this attempt to try and find some diagnostic label, some neat diagnostic box to put this person into and, and thus explain why they did this terrible, terrible thing.
NARRATOR: Josh Buckholtz is a Harvard neuroscientist searching for the biological roots of violence. For him and most experts, the rush to blame the shooting on Adam Lanza's rumored diagnosis of Asperger's syndrome was especially disturbing.
WOLF BLITZER (CNN/Film Clip): The medical examiner says he was told that Adam Lanza had been diagnosed with Asperger's syndrome.
STEVEN PINKER (Harvard University): The idea that the Newtown shooter was Asperger's, even if true, is utterly beside the point.
People who genuinely have Asperger's are not rampage killers.
JOSH BUCKHOLTZ: We know that we have millions of, of individuals who, who have that diagnosis who are not and will never become violent. So, science doesn't support that idea at all.
NARRATOR: So what will explain such an unspeakable act? Modern science has been trying to understand the minds of mass murderers for decades.
NEWS FOOTAGE (1966/Film Clip): And a human rampage spreads death and terror across the University of Texas campus. Twenty-four-year-old student Charles Whitman goes berserk, shooting…
NARRATOR: In 1966, ex-Marine Charles Whitman, after murdering his mother and wife, took a small arsenal to the top of a bell tower, at the heart of the University of Texas campus, and, inexplicably, opened fire.
NEWS FOOTAGE (1966/Film Clip): One afternoon's tragic total: 16 dead, 33 wounded.
NARRATOR: Whitman knew something was wrong with his mind. Remarkably, he left a note agonizing over his increasingly violent thoughts and requested an autopsy, expressing hope that doctors could find answers in his brain.
The results showed a nickel-sized abnormality pressing on a primitive part of the brain called the amygdala, which is crucial for generating some basic emotions.
JOSH BUCKHOLTZ: And so the thought was, "Ah ha! This was it. This amygdala lesion in Charles Whitman can explain his behavior..
NARRATOR: But over the decades, scientists realized, violence is not that simple. Today, with CT scans and M.R.I.s, researchers can peer deep inside the brains of violent criminals, revealing detailed anatomy and function. And using sophisticated analysis of many brains, they find some patterns.
JOSH BUCKHOLTZ: When we compare people who commit violent acts against people who don't commit violent acts, some brain differences begin to emerge: differences in brain circuitry that's involved in emotional arousal and emotion regulation.
NARRATOR: One of these circuits connects the pre-frontal cortex—responsible for higher-level thinking—to the amygdala, an emotional center, which goes into overdrive whenever a threat is perceived. If the threat is not real, the pre-frontal cortex will send a message to the amygdala to calm down, but if the wiring is faulty, that calming message may not get through.
JOSH BUCKHOLTZ: And in those folks, it seems like this circuit is broken in such a way that they're more likely to respond with greater amygdala activity and greater emotional arousal, when they think that they're being faced with some kind of threat.
NARRATOR: And this faulty wiring and violent behavior can also be associated with genes. In fact, Connecticut's medical examiner wants Adam Lanza's D.N.A. examined, but experts say, it's not likely to reveal anything definitive.
The frustrating truth is, although scientists can detect some patterns between brain wiring, genetics and violence, they only become clear when studying large groups of people, not individuals.
So is it possible to find some other way to determine who among us will turn violent? Surprisingly, experts say that the best answers may come, not from the scanners or genes, but from statistics called actuarials.
JOSH BUCKHOLTZ: Instead of turning to neuroscience, we can turn back to some, perhaps less sexy, but still very useful techniques that are derived, of all places, from, from insurance companies.
PAUL APPLEBAUM (Columbia University): There are characteristics that, when they occur together, markedly increase the risk of violent behavior: youth, male gender, substance abuse, a paranoid view of the world, hostility and difficulty controlling anger, preoccupation with weapons. Put those things together, and you've identified a group of people who are at much greater risk than the average person of committing a violent act.
NARRATOR: With rampage killers, there's another risk factor, one that, ironically, the media plays right into: a desire for fame and notoriety.
STEVEN PINKER: It is a guaranteed way to get fame. In fact, it's the only guaranteed way to gain fame. If you decide your life is worth nothing, you're a nobody, you haven't made a difference, and you want to do something that guarantees that your name will be on the lips of everyone in the country, what are your options? There's only one, and that is kill a lot of innocent people.
NARRATOR: So, knowing these risk factors, can we identify these potential killers and stop them, before they act.
PAUL APPLEBAUM: The problem is that there are tens of thousands of people who fall into that category, and the majority of them will never commit a violent act. And that's the limit of our predictive abilities today.
NARRATOR: So, without the ability to pinpoint potentially dangerous killers, what do scientists recommend? One obvious idea is to improve our mental health system.
NEWS VOICE (Film Clip): Circulating across social media today is a blog, written by Liza Long, called I Am Adam Lanza's Mother.
NARRATOR: The internet has been abuzz with parents recounting the challenges of finding treatment for potentially violent children.
PAUL APPLEBAUM: Parents are often forced to scramble to try to find a program that has room for their child, has appropriate services for their child, and is willing to treat their child.
NARRATOR: And this lack of mental health support, combined with an abundance of guns, can be deadly.
NELLY ALIA-KLEIN (Brookhaven National Laboratory): Sometimes, it's much easier to go into a store, like Walmart, and to purchase a gun than to make an appointment with the psychiatrist.
NARRATOR: Neuroscientist Nelly Alia-Klein studies people with intermittent explosive disorder, which can result in violent outbursts.
NELLY ALIA-KLEIN: So, a person who has aggressive traits and persistent, festering anger that is not treated, in combination with the availability of guns, can be a lethal combination.
NARRATOR: It is beyond today's scientific knowledge to say what would stop the next Adam Lanza. Improving mental health services is an important practical step, but many researchers who study risk assessment believe there's another obvious strategy.
PAUL APPLEBAUM: Even in the face of our difficulties of predicting and preventing violent behavior in general, there is an approach that we can take today that would markedly reduce the likelihood of horrific crimes, like what occurred in Newtown, Connecticut, from happening again. Were we to remove from easy access weapons that are designed solely for the purpose of killing large numbers of people—semi-automatic weapons, high volume clips, bullets intended to seriously maim and, and kill their victims—that could have an impact today, while we wait for the science to improve, while we wait to have a better capacity to identify people who are likely to behave in violent ways.
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Deadliest U.S. Mass Shootings
A look back at some of the most notable mass shootings in recent U.S. history: from Killeen, Texas, in 1991 to recent rampages at a movie theater in Aurora, Colo. and Sikh temple in Wisconsin.
"Exploring the Mind of James Holmes and the Tragedy in Colorado"
by Jerome Elam. The Washington Times , August 1, 2012.
"In Gun Debate, a Misguided Focus on Mental Illness"
by Richard A. Friedman, M.D. The New York Times , December 17, 2012.
"Can You Call a 9-Year-Old a Psychopath?"
by Jennifer Kahn. The New York Times Magazine , May 11, 2012.
"'I Am Adam Lanza's Mother': A Mom's Perspective on the Mental Illness Conversation in America"
by Liza Long. The Huffington Post (republished from The Blue Review), December 16, 2012.
"'I Am Adam Lanza's Psychiatrist': A Response from the Mental Health Trenches to 'I Am Adam Lanza's Mother'"
by Anonymous. xoJane.com, December 17, 2012.
"The Violent Brain: Ingredients of a Mass Murderer"
by Lauren Migliore. Brain World magazine, December 15, 2012.
"EXPERT: What Makes a Mass Killer?"
by Michael Welner, M.D. ABCNews.com, February 13, 2007.
"Mass shootings: Why it's so hard to predict who will snap"
by Stephanie Pappas. FOXNews.com, July 25, 2012.
"The Pain of Being Linked By Asperger Dx to a Mass Shooter"
by Lucy Berrington. Psychology Today , December 16, 2012.
"Mass Murders, Unlike Serial Killers, Are Hard to Profile"
by Lizzie Crocker. The Daily Beast , July 20, 2012.
"Can This Man Predict Whether or Not Your Child Will Become a Criminal?"
by Josh Fischman. The Chronicle Review , June 12, 2011.
"Good News and Bad News About Gun Laws, Mental Illness and Violence"
by Jeffrey Swanson, Ph. D. "Bill of Health" Harvard Law blog, October 5, 2012.
"Adam Lanza: Newtown Massacre Suspect a Puzzle to Authorities"
by Michael Daly. The Daily Beast , December 17, 2012
"Psychiatrist: Showing Video is 'Social Catastrophe'"
ABCNews.com, April 19, 2007.
"Notoriety Drives Mass Shooters"
by Mary Papenfuss. Newser.com, February 10, 2008.
"What Pushes Shooters Over the Edge?"
by Bill Weir. ABCNews.com, February 9, 2008.
"A Guide to Mass Shootings in America"
by Mark Follman, Gavin Aronsen, and Deanna Pan. Mother Jones , July 20, 2012.
"Current Directions in Violence Risk Assessment"
by Jennifer L. Skeem and John Monahan. Current Directions in Psychological Science , March 23, 2011.
"A Jurisprudence of Risk Assessment: Forecasting Harm among Prisoners, Predators, and Patients"
by John Monhan. Virginia Law Review , May 2006.
"Don't Blame Autism for Newtown"
by Priscilla Gilman. The New York Times , December 17, 2012.
"What Drives Suicidal Mass Killers"
by Adam Lankford. The New York Times , December 17, 2012.