Why did Bryan Kohberger kill? Experts weigh in on mysterious Idaho killings

USA Today

20-07-2025

As temperatures dipped below zero degrees less than two weeks before Thanksgiving, six college students were cozy in their bedrooms, resting up before the week's classes at the University of Idaho.
Creeping through the night, armed with a knife, Bryan Kohberger stalked them like helpless prey.
Kohberger moved through the house almost silently. He started the killing on the third floor with 21-year-old best friends and roommates Madison Morgan and Kaylee Goncalves. Then he came across 20-year-old Xana Kernodle on a stairway and killed her. Then he went into her bedroom, finding and killing her boyfriend, 20-year-old Ethan Chapin.
He left two others in the house alive.
Since the moment the families of the young victims learned about their seemingly random murders, their biggest question was why.
As Kohberger's sentencing approaches this week, USA TODAY is looking at the case and what could have possibly led a 28-year grad student with so much potential to butcher four people on one terrible night.
Nearly three years after the killings and a few weeks following a plea agreement that Kohberger reached with prosecutors, the families are still asking that same question. Kohberger's plea agreement – like most – doesn't require him to explain his actions.
But experts interviewed by USA TODAY agree that we can conclude a lot about Kohberger's motives based on the evidence and his history: He was bullied, he felt rage toward women, he fantasized about violence and ultimately, wanted power more than anything, they say.
"A lot of killers feel powerless their whole lives and that's why killers become serial killers. Because for the first time they feel like an all-powerful god," said Rachel Toles, a clinical psychologist and criminal expert based in Greenville, South Carolina. "He wanted to feel powerful for once in his life."
What happened the night of Nov. 13, 2022?
Mogen, Goncalves, Kernodle and Chapin were found stabbed to death on Nov. 13, 2022, in a rental house in the quiet city of Moscow, Idaho, near the University of Idaho campus.
DNA evidence, cell phone records and surveillance footage tied Kohberger to the stabbings, prosecutors said.
Why did Bryan Kohberger become a killer?
Kohberger's past tells us a lot about his motivations, experts say. During his childhood, he was isolated and bullied and eventually became addicted to heroin and struggled with his weight.
At some point he was able to kick the heroin habit, lose weight and get lean, according to the 2025 book, "The Idaho Four: An American Tragedy."
"He grew up kind of bullied, kind of ostracized and he decided to change his life ... and I think he started viewing himself as a possessor of power. Before he was someone without power and now he possesses it," said John Delatorre, a psychologist based in San Antonio, Texas, who works on criminal cases.
Ultimately, "he viewed himself as someone who could take what he wanted whenever he wanted," Delatorre said. "I think what interested him was the idea that you could legitimately hold someone's life in your hands and take it away whenever you choose to do so."
Toles added: "He probably also wanted revenge on a world that made him feel unwanted."
Kohberger's past addiction, weight gain and loss, Toles said, also show that he "clearly felt empty his whole life" and may have been attracted to studying criminology at the University of Washington because it "gave him a language for his alienation."
Kohberger seemed particularly interested in three killers: Ted Bundy, the BTK Killer and Elliot Rodger. Through them, he identified with a narrative arc that "rejection moves to resentment moves to obsession moves to control moves to violence moves to infamy," Toles said.
"It's a storyline he could place himself in and one that made him feel more powerful instead of invisible," she said, adding that Kohberger may have thought: "Maybe I'm not a problem. Maybe I'm like them. Maybe I'm a predator."
Kohberger likely felt the urge to kill for years, Delatorre said, relying on fantasies and stalking before he ultimately acted on it.
"The idea of taking someone's life with a knife was probably something he was think about for quite some time, it just required a target," he said. "People don't snap. People brew, they fester. The negative emotionality is over a long period of time to get them to a breaking point to act out."
What is happening with the case?
Kohberger, 30, pleaded guilty to the killings earlier this month after accepting a plea agreement that allowed him to avoid the death penalty and instead face four consecutive life sentences.
The agreement also means he'll avoid a lengthy and highly publicized trial.
He's scheduled to be officially sentenced on Wednesday, July 23. The families of the victims will be allowed to address the court at that time to talk about the impact of the crime and who their loved ones were.
What have the victims' families said?
Many of the victim family members were surprised by and upset with the plea agreement.
"This is anything but justice," Steve Goncalves, the father of victim Kaylee Goncalves, told NewsNation's "Banfield."
"We had an outsider come to our community, kill our kids in their sleep while they're getting a college education, doing everything that they should do, and we don't have the courage to hold him accountable," he said.
Some family members felt the plea agreement was a good thing and avoided the pain of a trial and prolonged legal process.
Kernodle's mother, Cara Northington, told Fox News: 'The death penalty would give him the opportunity to appeal and drag this horror story out for the rest of our lives."
Amanda Lee Myers is a senior crime reporter for USA TODAY. Follow her on X at @amandaleeusat.