Defense and prosecution argued Friday over murder suspect Bryan Kohberger’s motion to compel the state to provide all records related to its use of DNA to tie him to the crime scene.
Kohberger is charged with the murders of University of Idaho students Kaylee Goncalves, Ethan Chapin, Madison Mogen and Xana Kernodle at an off-campus house on Nov. 13, 2022.
The Latah County District Court held a motion hearing Friday for Kohberger.
While Judge John Judge heard several motions, the hearing centered on the defense’s motion to compel the state to provide all records related to its use of investigative genetic genealogy that led them to link Kohberger to the crime scene.
Prosecutors said the submission of DNA found on a knife sheath at the crime scene to the FBI database yielded no results so they turned to another method that involves building a DNA profile that could be used to search for relatives. They then submitted the profile to multiple genetic genealogy services that allowed them to create a family tree of hundreds of relatives and established Kohberger as a suspect. This was affirmed when they compared the DNA to a sample taken from his father and then directly to Kohberger when the suspect provided a cheek swab during his arrest.
The state has objected to the defense’s motion with Latah County Prosecuting Attorney Bill Thompson saying that is no legal requirement to disclose all DNA records.
The defense’s request also included the mention of three undisclosed male samples. The state, however, denies that such samples exist.
In Friday’s hearing, the defense also provided two expert witnesses: criminal defense attorney and DNA database specialist Stephen Mercer and IGG expert Leah Larkin. Mercer testified to the court that the release of IGG records is the minimum practice standard. Larkin offered a breakdown of how family trees are produced through DNA evidence.
Larkin wrote an affidavit in early August that cast doubt on the reliability of the IGG process.
She wrote that genealogy tests are not as reliable as short tandem repeat standard forensic tests.
“The best-case scenario for the defense is that the expert testimony on each side confuses the jury regarding the issue of DNA science such that the confusion raises some doubt regarding the damning DNA evidence against Kohberger,” Criminal Defense Attorney Rachel Fiset told Newsweek.
Kohberger’s trial is set for Oct. 2 and is scheduled to last for about six weeks.