Neuroscientist Michael S. Gazzaniga explains why some people may be born criminals.

A Neuroscientist Explains Why Some People May Be Born Criminals

A Neuroscientist Explains Why Some People May Be Born Criminals

The citizen’s guide to the future.
Nov. 15 2011 11:17 AM

Not Guilty by Reason of Neuroscience

Some people’s brains may doom them to a life of crime.

Who's In Charge?

From the book Who’s in Charge?: Free Will and the Science of the Brain, by Michael S. Gazzaniga. Copyright © 2011 by Michael S. Gazzaniga. Reprinted by permission of Ecco, an imprint of HarperCollins Publishers.

On Feb. 19, 1997, a house painter called 911 in Tampa, Fla. He had returned unannounced to a client’s house and through a window saw what appeared to be a naked man throttling a naked woman. When the police arrived, they learned the man hadn’t just strangled Roxanne Hayes; he had stabbed the mother-of-three multiple times, killing her.

The murderer’s name was Lawrence Singleton; he was 69 years old, and he was notorious in California, where 19 years before, he had raped a 15-year-old hitchhiker, Mary Vincent; hacked off her forearms; and left her in a canyon to die. Two vacationers came across her the next morning, walking naked toward the interstate, the stumps of her severed arms raised to prevent further blood loss. Vincent’s description of her attacker was so vivid that it resulted in a police artist’s drawing that his neighbor recognized. Singleton was tried, found guilty, and given what was the maximum sentence at the time in California of 14 years. He was released on parole, however, after eight years of “good behavior,” even though shortly before his release a prison psychiatric evaluation read, “Because he is so out of touch with his hostility and anger, he remains an elevated threat to others’ safety inside and outside prison.” Mary’s mother, Lucy Vincent, said that Mary’s father would carry a .45-caliber pistol and often contemplated killing Singleton.


Because Singleton had written letters to her lawyer threatening her while he was in prison, Mary was terrified after his parole. So were Californians. Residents of every California town that prison authorities tried to settle him in staged angry protests. He was finally settled in a mobile home on the grounds of San Quentin prison until his parole was up and he moved to Florida.

In 2001 Singleton died of cancer while on death row in Florida. Mary Vincent told a reporter that his arrest and death had given her a “tremendous feeling of freedom,” but that she still had such vivid nightmares (during which she had actually dislocated her shoulder, cracked ribs, and smashed her nose) that she was afraid to go to sleep. Divorced, with prostheses that she has modified with spare parts from broken refrigerators and stereo systems, she is now an artist struggling to support two sons.

While you read this, what were your gut feelings and thoughts about Larry Singleton? Did you want him to be locked up and never released (incapacitation)? If you had been Mary’s father, would you, too, have wanted to kill him (retribution)? Or did you want to forgive him, to tell him that it is too bad his brain was unable to inhibit his naturally aggressive tendencies and that perhaps with some treatment he could be more prosocial (rehabilitation)?

Incapacitation, retribution, or rehabilitation are the three choices society has for dealing with criminal behavior. When society considers public safety, it is faced with the decision about which perspective those making and enforcing the laws should take: retribution, an approach focused on punishment of the individual and just desserts; or consequentialism, a utilitarian approach that what is right is what has the best consequences for society.

Neuroscience is beginning to challenge some people’s notions about criminal behavior and what we should do about it. Determinism—the belief that all current and future events, actions, decisions, and behavior are caused by preceding events combined with the laws of nature—disputes long-standing beliefs about what it means to be responsible for one’s actions; some scholars assert the extreme view that humans are never responsible for any of their actions. These ideas challenge the very foundational rules regulating how we live together in social groups. Should people be held accountable for their behavior? If they aren’t, it seems that it would change behavior for the worse, just as studies show that merely reading about determinism results in increased cheating on tests. Is accountability what keeps us civilized? Neuroscience has more and more to say about these questions and is already slowly oozing into the courtroom—prematurely, to the view of most neuroscientists.