Over the years, neurobiologists have identified several factors that are highly correlated or associated with violent behavior in people:
Each one of these correlates of violence, or factors which are often found in combination with it, has been observed among violent criminals and murderers over the years. Although these factors are scientifically linked to violent behavior, none of them, individually or collectively, should be considered sufficient or even necessary for an individual to become violent.
Forensic psychologists have discovered that certain key traits of violent behavior are very consistent with an antisocial personality disorder known as psychopathy. This disorder is manifested in certain distinct and troublesome behavioral traits and characteristics.
Psychopathy is not classified as a mental illness by the American Psychiatric Association (APA). The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), released by the APA in 2013, lists psychopathy under the heading of Antisocial Personality Disorders (ASPD).
The APA estimates that approximately one percent of the adult population in the U.S. are psychopaths. Generally speaking, psychopaths are intelligent, glib, and charming and use these attributes to manipulate others into trusting and believing in them. Because they often have strong interpersonal skills, psychopaths can present themselves quite favorably on a first impression and often function very successfully in society.
However, a number of attitudes and behaviors common to psychopaths are distinctly predatory in nature: They tend to view others as either competitive predators or prey. When psychopaths view others as prey, their lack of feeling and bonding to others provides them unusual clarity in observing the behavior of intended victims. Moreover, they do not become encumbered by the anxieties and emotions that other people experience in interpersonal encounters.
Psychopaths are unable to form emotional attachments or feel real empathy with others, despite their disarming or even charming personalities. Psychopathy is the most dangerous of antisocial personality disorders because psychopaths are very manipulative and can easily gain people’s trust. They learn to mimic emotions, despite their inability to actually feel them, and appear normal to unsuspecting people. Psychopaths are often well educated and hold steady jobs. Some are so good at manipulation and mimicry that they have families and other long-term relationships, and those around them never suspect their true nature.
When committing crimes, psychopaths carefully plan out every detail in advance and often have contingency plans in place. Psychopathic criminals tend to be cool, calm, and meticulous. They make few mistakes and are never undone by their emotions.
Not surprisingly, psychopaths are overrepresented among serial killers. When a psychopath becomes a serial killer, he or she will most likely be found among the FBI’s “organized” killers, who tend to be cold-blooded, meticulous planners. Charming, unflappable psychopath Ted Bundy is a classic example of a poised, articulate, and highly organized serial killer.
It is believed that psychopathy is the result of “nature” (genetics) rather than “nurture” (environment). According to the late David Lykken, a behavioral geneticist known for his studies involving twins, psychopathy is related to a physiological defect that results in the underdevelopment of the part of the brain responsible for impulse control and emotions.
As a result of this disorder, psychopaths are incapable of empathy and unable to form emotional bonds with anyone. Ironically, and frighteningly, it is the uncanny ability of psychopaths to mimic empathy with others that makes them especially dangerous and successful serial killers. Because they are so disarming and seemingly nonthreatening, the psychopathic predator causes us to lower our guard and put ourselves at greater risk to their brutality.
I examine the public’s intense fascination with notorious and deadly serial killers, including David Berkowitz (“Son of Sam”) and Dennis Rader (“Bind, Torture, Kill”), with whom I personally corresponded, in my book, Why We Love Serial Killers: The Curious Appeal of the World’s Most Savage Murderers.
In a forthcoming book, tentatively titled Women We Love to Hate: Jodi Arias, Pamela Smart, Casey Anthony and Others, I explore the intense fascination with female killers and why they are demonized by the media and much of the public. More specifically, I examine the social processes that transform certain attractive, young, white females charged with murder into high-profile, celebrity monsters.
Dr. Scott Bonn is professor of sociology and criminology at Drew University. He is available for expert consultation and media commentary. Follow him @DocBonn on Twitter and visit his website docbonn.com