BOISE, Idaho — After three decades as the prosecutor of Latah County, Idaho, Bill Thompson's long career culminated in an emotional moment during Bryan Kohberger's sentencing hearing.
As Dylan Mortensen, one of the surviving housemates in the brutal 2022 fatal stabbing of four University of Idaho students at an off-campus house, gave her first public statements since the murders in a Boise courtroom Wednesday, Thompson sat beside her at the prosecutors' table and intentionally leaned forward. Kohberger could not see her as she spoke through tears, even though Mortensen was only a few feet away from the man who pleaded guilty to slaughtering her friends.
"I had been asked to block his view of her, so she made her statements at the court," Thompson told NBC News during an interview Thursday. "That was something I've never experienced before — watching the strength of that young lady describing not only what happened that night, but what her life has been, the hell her life has been since then."
"A 19-year-old girl having to live through this, and for her to come out with so much strength and so much class," he added, "pretty darn impressive."
Mortensen, now 21, described the anxiety and guilt she felt having lived through the murders in the house in the college town of Moscow that garnered international headlines. She had told police she had seen a masked intruder dressed in black, but did not realize what had occurred until hours later.
At the sentencing, she did not use Kohberger's name in the victim impact statement, but called him a "hollow vessel, something less than human, a body without empathy, without remorse."
Thompson told NBC News that many unanswered questions surrounding the case remain a mystery, including why Kohberger left the murder scene without harming either Mortensen or another housemate, Bethany Funke, whose victim impact statement was read in court by a friend.
"I'm sure there are theories," Thompson said. "Dylan had an angel watching over her."
In the wake of the sentencing, the Moscow Police Department released more than 300 documents from its investigative files, detailing how law enforcement officials collected evidence against Kohberger, now 30, in the murders of seniors Kaylee Goncalves and Madison Mogen, both 21; junior Xana Kernodle, 20; and Kernodle's boyfriend, freshman Ethan Chapin, 20.
Prosecutors said they had DNA, cellphone use, online shopping history and surveillance video among the evidence tying Kohberger to the crime scene, although nothing indicating that he knew his victims.
Kohberger, a former doctoral student in criminal justice at nearby Washington State University, pleaded guilty to the quadruple murders and waived his right to appeal in a deal that spared him a trial next month and the death penalty.
Instead, a judge Wednesday sentenced him to four consecutive life sentences without parole, plus a 10-year sentence for burglary.
Thompson, who had previously planned to retire but stayed on to see the case through, has faced criticism from some of the victims' families who wanted Kohberger to go to trial, and also believe any agreement should have included the defendant providing a motive for the crime.
However, the prosecutor told NBC News that it wasn't his team that brought up the idea of a deal, but rather defense lawyers who approached him in June, with only weeks before jury selection was slated to begin.
"Up to that point, the defense had maintained consistently that they believed their client was factually innocent of the charges, so there was nothing to discuss," Thompson said. "We were simply preparing for trial."
Kohberger's lead attorney, Anne Taylor, did not immediately respond to a request for comment Friday. Her office previously stated that it would not be speaking following the sentencing, as a sweeping gag order that had long prevented law enforcement and lawyers from making public statements about the case had been earlier vacated.
Steve Goncalves, the father of Kaylee Goncalves, told reporters after the sentencing that the state had made "a deal with the devil" about Kohberger.
But Thompson refuted the idea that the defendant was able to negotiate.
"We made a proposal on our terms, not his," Thompson said. "We told his lawyers that the only possible resolution short of going to trial is for him to plead guilty as charged and to waive his appeals, and that we would be seeking fixed, consecutive life sentences. That's the discussion we had, and they took that back to their client and came to us and said that he's prepared to plead guilty."
In late June, the judge had rejected the defense's ability to present four "alternate perpetrators" at trial, describing the theories as "entirely irrelevant"; it was the latest setback in a series of them for the defense's case.
Thompson said he had no idea why Kohberger ultimately took the plea deal. Much about Kohberger remains an enigma, he added.
"It would always be nice to have an answer to everything, but the reality is, is that we don't always have that luxury," Thompson said.
While the newly released police documents don't shed light on why Kohberger chose his targets, they explain how in the weeks before the killings, Kaylee Goncalves had recounted a series of unnerving events to the two surviving roommates: She had mentioned that she believed someone was following her two or three weeks before the stabbings, and that she saw a shadow while she was outside with her dog about a month before the murders.
Whether those events are definitively linked to Kohberger remains unclear.
"Having people out and about in the neighborhood isn't going to be unusual," Thompson said. "I think that the roommates and Kaylee's sense that something was amiss probably was accurate, but I don't think that we can do anything more than just recognize that."
Other speculation about motive also may never be fully understood, Thompson added.
Investigators have said there was no evidence of sexual assault against any of the victims.
"I suppose anything could have been going through Mr. Kohberger's mind at the time, but we don't know what that was," Thompson said.
The prosecutor, however, added that he "doesn't care" if Kohberger chooses to tell his story from prison one day, either to the media or through a book or other public forum.
"I say that not to be cavalier, because I will feel for the families if he tries to make to write a book and profit off of it," Thompson said. "And there are laws in Idaho that we can use to help control that, and we've already had these discussions with the families. My preference is that he just disappears into the Idaho Department of Corrections."
Kohberger was transferred to the Idaho Maximum Security Institution near Boise after the sentencing, where he may serve his life sentences in a form of solitary confinement.
But despite the grisly case, Thompson admitted Kohberger's demeanor still struck him at the sentencing. As the family of the victims spoke, some in tears and others delivering blistering verbal attacks, Kohberger appeared emotionless.
Thompson, himself, could not help but cry as the loved ones talked about the victims and their futures — the graduations, birthdays, marriages, children — that were lost.
"There's no way that a normal human being would not feel overwhelming emotion and sympathy for these poor victims and for the surviving roommates and for the community and the betrayal and the harm that can never be undone, that everybody has to live with going forward, that's part of being humans," Thompson said. "We recognize that, and we're all going to suffer somehow with it."
Liz Kreutz reported from Boise and Erik Ortiz from New York.
