Jeffrey Landrigan was finally executed in 2010.
Why do people kill? This isn't an easy question to answer, but criminologist Adrian Raine believes some people are pre-programmed to be violent.
He has written a new book on the subject — "The Anatomy of Violence" — which relays an eerie story of a now-executed murderer that seems to back up his theory of a "killer gene."
That executed murderer is Jeffrey Landrigan, who was adopted as an infant by an attentive mother and a respectable geologist in 1962. His adoptive family in Oklahoma was educated and "straight-laced," Raine writes.
But "murder seemed almost destiny" for him, Raine writes. When Landrigan was 20 years old, he got drunk and stabbed a childhood friend to death.
He got a 20-year sentence but managed to escape prison.
In 1989 he killed a gay health club worker in Phoenix. Landrigan was caught and got the death penalty.
Landrigan made a shocking discovery on death row: his biological father was a murderer too. He also discovered his grandfather was a violent criminal, Raine writes. Landrigan made the discovery when another inmate on death row told him he looked exactly like a man named Darrel Hill, who was on death row in Arkansas.
Hill was in fact his father, according to Raine's book and multiple news accounts. Hill had also committed murder multiple times. He'd even escaped from prison like his biological son. Landrigan's grandfather was a career criminal who was killed by police after a robbery in 1961.
Even though he was raised by a loving family, Landrigan still followed in his father's and grandfather's terrible footsteps. Here's Raine's take on the significance of his discovery:
This fascinating natural experiment — in which a baby with a violent heritage was transferred from a life of poverty and squalor into a loving, caring, successful family, yet still became a killer — suggests that there really is a genetic predisposition to violence.
After discovering his violent heritage, Landrigan tried to use his family history of crime to get off death row. In 1999, he tried to convince a court he'd inherited a "killer gene" from his dad, the Sunday Mirror reported at the time.
"I've never met my father. But he was definitely, even without being there, a big influence in my life," Landrigan told the Mirror from his prison cell.
Landrigan's case is a stunning example of the possible genetic roots of violence. But there are actually "hundreds of Jeffrey Landrigans" out there, Raine writes. About a dozen studies have shown that adopted children whose parents were criminals were more likely to commit crimes than adopted children whose biological parents weren't criminals, he writes.
This is definitely sobering news for anybody who's considering adoption.
But Raine says there are ways to stop people who are predisposed to violence from actually becoming criminals. Biology might be a blueprint, but it's not necessarily destiny.
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