A public rift has emerged between Bryan Kohberger’s defense lawyers and a hired expert witness after Kohberger’s guilty plea in the murders of four University of Idaho students.

In their first public statement made outside the courtroom since Kohberger’s arrest in December 2022, Kohberger’s lawyers have accused a former defense expert, criminologist Brent Turvey, of violating a confidentiality agreement by speaking about the case.

“Mr. Turvey has not been released from his confidentiality agreement, and is now speaking about topics that are still confidential, many of which are outside of his areas of expertise,” a statement signed by Kohberger attorneys Anne Taylor, Elisa Massoth and Bicka Barlow said.

Turvey is a forensic scientist with a Ph.D. in criminology. In a fiery statement released Tuesday evening, Kohberger’s lawyers wrote that they are “appalled” by his recent comments.

“It is the opinion of the defense team that Mr. Turvey’s conduct falls outside of the ethical and legal norms that are applied to experts in criminal cases, and his reliability should be seen through the lens of this conduct,” they wrote.

Turvey has spoken with a number of news outlets in recent days, including Fox News Digital, after breaking his silence in a newly released book about the case by former FBI agent Christopher Whitcomb, “Broken Plea,” which revealed a defense assertion that there were serious problems with the chief piece of physical evidence in the case.

In those interviews, Turvey discussed evidence he reviewed for the defense and internal disagreements over testing and strategy, prompting the rare statement from Taylor, Massoth and Barlow.

However, he denied that he divulged any confidential information and alleged that Taylor’s office was under investigation over a leak of confidential video before Kohberger’s guilty plea in violation of a restrictive gag order.

“Her press release comes as a bit of a surprise given that nothing confidential was revealed by me,” he told Fox News Digital.

In addition to denying he divulged any confidential material, he mentioned that Taylor’s office had been investigated in connection with a leak of investigative materials to Dateline last year. The prosecution team had also been investigated over the incident, and the court has not publicly identified the leaker.

“I know that the NBC evidence link was not me, and I’ve sworn an affidavit to that effect for the court’s administrative investigation which has been completed, but the results sealed,” Turvey said. 

“The most bizarre part of Anne Taylor’s press release is that she makes an allegation without being specific or providing any evidence. It’s not just false and unprofessional. It likely violates her own ethics as an attorney and the law if she is alleging a crime.”

He said the topics he’s been speaking about have been “buried in mass public disclosures.”

The major revelation in “Broken Plea” stems from a purported chain of custody problem with Kohberger’s Ka-Bar knife sheath, which had his DNA under the snap. It was not mentioned in Turvey’s expert report, which he said was filed before he learned of it.

The evidence bag appears to have been filled in twice — once on the bag itself, and later on a sticker attached to the front.

The earliest date visible on the bag is “11/14/22,” alongside the initials “BP,” likely belonging to lead detective Brett Payne. It was written over the evidence tape sealing the bag.

The label, affixed sometime later, has six recorded exchanges between Nov. 13 and Nov. 16 written with a single pen in similar handwriting, according to Turvey.

Turvey maintains that should have made it inadmissible.

Had Kohberger’s case gone to trial, prosecutors would have challenged his findings, which have not been evaluated by a judge or jury. Experts have downplayed the significance of his claims.

Paul Mauro, a retired NYPD inspector and Fox News contributor, reviewed images of the chain of custody forms and said he didn’t see a significant problem for the prosecution

“What it could point to is that is a vulnerability in the case, so they take a plea,” he said. “They could have been concerned about losing a juror on that. On the other hand, it’s very indicative of what you do when you have absolutely no defense. You put the procedure on trial, instead of the facts.”

Turvey said his rift with Taylor goes back to around the time of Kohberger’s plea deal. She had not pursued his chain of custody concerns or DNA testing he wanted for additional hair evidence.

“Until we had the first and only all team member meeting, the day after the plea agreement, we were in excellent terms and in a place of complete confidence and professional trust as far as I was concerned,” he said. “Things took a dramatic turn during that meeting.”

He declined to discuss specifics but said previously that the plea deal came as a surprise to him and despite his chain of custody concerns and a push to have additional DNA testing performed.

Taylor did not immediately return a call seeking comment.

Kohberger admitted to the murders of Madison Mogen, 21, Kaylee Goncalves, 21, Xana Kernodle, 20, and Ethan Chapin, 20, on July 2, 2025.

He took a plea deal that spared him from the potential death penalty. He forfeited his right to appeal. He gave no explanation for the crimes and sat expressionless through sentencing weeks later as the victims’ families read scathing impact statements in court.

On the night of the murders, he searched Google for local police dispatch audio, according to public records tied to the case. He powered off his phone before the murders and turned it back on after them. While investigators found none of the victims’ DNA in his car after they seized it in Pennsylvania, an FBI analyst determined soil on a shovel found inside it matched dirt from the Moscow area.

“Truth be told, I’m unable to come up with anything redeeming about Mr. Kohberger,” Judge Steven Hippler said at sentencing. “His grotesque acts of evil have buried and hidden anything that might have been good or intrinsically human about him.”

Hippler handed down a sentence of four consecutive terms of life in prison with no parole, plus another 10 years.