Bryan Kohberger's motive: What we know after guilty plea

Bryan Kohberger has agreed to plead guilty to killing four University of Idaho students in Moscow, Idaho, more than two and a half years after the quadruple stabbing shocked the small farming town. 

On Wednesday, the lead prosecutor on the case presented his key evidence at a court hearing, detailing what led investigators to charge Kohberger with killing Kaylee Goncalves, Ethan Chapin, Xana Kernodle and Madison Mogen in their rental home near campus on Nov. 13, 2022.

Kohberger’s guilty plea allows him to avoid the death penalty, but it also leaves a lot of questions that could have been answered at trial. 

Bryan Kohberger, charged in the murders of four University of Idaho students in 2022, appears for a hearing at the Ada County Courthouse on July 2, 2025, in Boise, Idaho. Kohberger has agreed to plead guilty in exchange for being spared the death pen

What was Kohberger’s motive? 

What we know:

Kohberger, now 30, had begun a doctoral degree in criminal justice at nearby Washington State University — across the state line from Moscow, Idaho — months before the crimes.

RELATED: Bryan Kohberger accepts plea deal in Idaho student murders case

What they're saying:

"The defendant has studied crime," lead prosecutor Bill Thompson said. "In fact, he did a detailed paper on crime scene processing when he was working on his Ph.D., and he had that knowledge skillset.

What we don't know:

Although prosecutors have painted a clearer picture of what happened that night, they still haven’t answered why Kohberger picked that house and those victims. They also haven’t said whether Kohberger knew any of the people he reportedly killed. 

"We do not have evidence that the defendant had direct contact with 1122 or with residents in 1122, but we can put his phone in the area on those times," Thompson said, referring to the house number where the murders took place.

What did Kohberger do after he killed them? 

Dig deeper:

While the motive remains unclear, prosecutors say Kohberger went to great lengths to cover up his heinous crimes. 

He reportedly drove backroads to his apartment in Pullman, Washington, to avoid surveillance cameras on the major roads and didn't turn his cell phone back on until 4:48 a.m. By 5:26 a.m., he was back in Pullman, Thompson said.

Later, Kohberger changed his car registration from Pennsylvania to Washington State — significant for investigators who were combing through surveillance camera footage because Pennsylvania law doesn't require a front license plate, making it harder to identify the vehicle.

And by the time investigators did catch up with him weeks later, his apartment and office in nearby Pullman were scrubbed clean.

"Spartan would be a kind characterization. There was nothing there, nothing of evidentiary value was found," Thompson said of Kohberger’s apartment.

The car, too, "had been essentially disassembled inside," he added. "It was spotless. The defendant’s car had been meticulously cleaned inside."

DNA on Q-tip links Kohberger to crime scene

The night of the murders, Kohberger left behind the knife sheath that held the murder weapon, and along with it his DNA. 

Investigators worked with the FBI and a local sanitation department to secretly retrieve garbage from the Pennsylvania home of Kohberger's parents, conducting a "trash pull" during the night that led them to a Q-tip used by Kohberger’s father. 

That was enough for authorities to arrest Kohberger at his parents’ home in Pennsylvania. He had driven there for the holidays after the murders. 

Victims’ families react to plea deal

The victims’ families are divided over the plea deal. 

Chapin's and Mogen's families support the deal.

RELATED: Bryan Kohberger plea deal angers victims' families

"We now embark on a new path. We embark on a path of hope and healing," Mogen's family said in a statement.

The other side:

The family of Kaylee Goncalves publicly denounced the plea deal ahead of Wednesday's hearing and her father refused to attend the proceedings.

Goncalves 18-year-old sister, Aubrie Goncalves, said in a Facebook post that "Bryan Kohberger facing a life in prison means he would still get to speak, form relationships, and engage with the world."

"Meanwhile, our loved ones have been silenced forever," she wrote.

Will we ever know Kohberger’s motive? 

What's next:

Some of the evidence that won’t come out at trial might still be found in court documents, but those remain sealed until after a July 23 sentencing hearing. A gag order in place for all attorneys in the case is still in effect as well.

Those documents include witness lists, a list of exhibits, an analysis of the evidence, requests for additional discovery, filings about mitigating factors and various unsuccessful defense motions that sought to introduce alternative suspects, among other things.

It’s not clear whether Kohberger’s motive for the grisly killings will be revealed when the gag order is lifted. 

The Source: This report includes information from The Associated Press and previous LiveNow from FOX reporting. 

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