DNA found on a Ka-Bar knife sheath found under the body of a murder victim in the Idaho Four case is a ‘statistical match’ with Bryan Kohberger, the man charged in the murders, prosecutors say in a new court case.
The revelation of the DNA evidence came in a motion for a protective order sought by prosecutors. They do not want to release information regarding the investigative genetic genealogy used in the case to Kohberger’s defense.
“The state seeks to protect from disclosure the names and personal information of the hundreds of innocent relatives listed in the family tree, the names of the publicly available genetic genealogy services used, and certain other information,” prosecutors wrote in the request.
Kohberger, 28, faces one count of burglary and four counts of first-degree murder in the murders of four University of Idaho students. Housemates found the bodies of Maddie Mogen, Kaylee Goncalves, Xana Kernodle and Ethan Chapin on the morning of Nov. 13, 2022. All had been stabbed to death, some while they slept, Moscow police.
“Statistical Match”
Prosecutors say the DNA on the knife sheath is a “statistical match” to a sample taken from Kohberger’s cheek after his arrest. The probable cause affidavit charging Kohberger with the murders last December said the profile on the sheath belonged to the child of Kohberger’s father. The agents had developed the DNA profile of Michael Kohberger from elements taken from his trash.
Prosecutors explain in the motion how the Idaho State Crime Lab developed a DNA profile from the knife sheath. This sheath, they claim, was found partially under Maddie Mogen’s body and her quilt. Idaho State Police located the DNA profile on the sheath and determined it was from a single source and from a male.
Then the Idaho State Police contacted a private lab to develop a DNA profile used in genealogy, SNP. This action was taken after the police could not find a match with the profile found in the Combined DNA Index System or CODIS, which contains the profiles of known criminals.
According to the petition, the FBI took over the genetic genealogy process after obtaining the SNP profile from the private lab. From there, officers created family trees using publicly available tools and data.
“Much of the information relied upon by the FBI was accessed only through the user portal of the publicly available genetic genealogy service(s) and other investigative databases. The FBI has not downloaded or created copies of these recordings,” the motion reads.

Bryan Kohberger is taken away by sheriff’s deputies from the Monroe County Courthouse in Stroudsburg, Pennsylvania on January 3, 2023.
“Look at Everything”
Prosecutors say that process did not generate documents and is not covered by Idaho’s Rule 16. This rule governs the material that must be turned over to the defence.
“I could see wanting to keep innocent parties off the public record for a criminal case,” said James Bogen, a criminal defense attorney who has followed the case. “As a defense attorney, you want to be able to review anything that might be relevant to the evidence in the case.”
Prosecutors later write that they don’t want to ban the publication of other DNA-testing-related material — only information related to genetic genealogy. The defense requested the information.
Kohberger “kept silent”
Meanwhile, defense attorneys and prosecutors are at odds over the grand jury papers. The two sides can’t agree on what the defense should be.
Defense attorney Anne Taylor asked to stay proceedings on the issue. Kohberger’s trial is scheduled for October 2. Taylor said in a motion that this was causing a delay and that Kohberger was “staying silent” during his arraignment so he could challenge the indictment.
A hearing on the grand jury issue is scheduled for Tuesday, June 27 at 1:30 p.m. PDT.
Do you have a tip we should know? [email protected]