BOISE, Idaho — In hearings this week that will likely set the table for his summer murder trial, Bryan Kohberger and his attorneys will return to the courtroom for the first time in more than two months to argue for excluding a host of evidence.

Since November, the defense and prosecution have traded legal briefs over the disputed evidence in the University of Idaho student homicides case. The pieces the defense wants suppressed include: DNA taken from Kohberger that the state says matches some from the crime scene in Moscow where the four college students were killed; every item seized from his college apartment, car and parents’ Pennsylvania home; and all the information from his cellphone and online footprint obtained through search warrants.

The defense has asserted that all of this evidence — and still more, including from two search warrants for Kohberger’s person when he was briefly jailed in Pennsylvania, and again when he was brought to Idaho to await trial — should be withheld from a jury over alleged police misconduct.

Kohberger, who turned 30 in November, has now spent over two years in custody since his arrest in late 2022 on suspicion of the fatal stabbings that took place in the early-morning hours of Nov. 13 that year. He faces four counts of first-degree murder and one count of felony burglary, and could be sentenced to death if convicted.

The victims were Madison Mogen, 21, of Coeur d’Alene; Kaylee Goncalves, 21, of Rathdrum; Xana Kernodle, 20, of Post Falls; and Ethan Chapin, 20, of Mount Vernon, Washington. The three women lived in the King Road house just off campus in Moscow where the killings occurred. Chapin was Kernodle’s boyfriend and stayed over for the night.

At the time, Kohberger was a Ph.D. student of criminal justice and criminology at Washington State University and lived in Pullman, Washington, about 9 miles west of Moscow. Eleven days after police first arrived at Kohberger as a suspect, they arrested him at his parents’ home in Pennsylvania while he visited them on a break from school.

Detectives working the quadruple homicide case “intentionally or recklessly omitted” certain details from the investigation to convince a judge of probable cause for search warrants, Kohberger’s defense said in court filings. In addition, some of the warrants weren’t as specific as required by the law about what they sought, wrote his attorneys.

And, in what would prove most damaging to the prosecution if accepted by the judge, the defense is seeking to block use of their client’s genetic information in the case. Filed under seal, his attorneys argued that Kohberger’s Fourth Amendment rights against unreasonable search and seizure were infringed upon when the FBI pursued an advanced DNA technique called investigative genetic genealogy, or IGG, by using public ancestry websites to narrow the list of possible suspects.

Police obtained most of the other evidence through search warrants after IGG first led them to Kohberger as the suspect on Dec. 19, five weeks after the students’ deaths, according to recent defense filings. His attorneys argued all of that should be thrown out as a result of initially violating their client’s constitutional rights.

Led by Latah County Prosecutor Bill Thompson, state attorneys contested the defense’s arguments to suppress any of the evidence and disputed claims that police did not follow proper procedures during the investigation. The probable cause affidavit for Kohberger’s arrest did not mention the use of IGG, but it was not intended as evidence at trial, Thompson said, and also wasn’t used as justification for any search warrants.

The defense last week filed a motion to unseal the two sides’ IGG suppression filings, and asked that the hearing on that evidence be held in open court. In response, 4th District Judge Steve Hippler set a closed-door hearing for Tuesday at 10 a.m. at the Ada County Courthouse to decide how to proceed ahead of a previously scheduled public hearing for oral arguments on the evidence suppression issue, set for Thursday morning.

Fourth Amendment challenge of IGG long foreseen

Anticipating a Fourth Amendment argument over the FBI’s use of IGG in the high-profile case, Thompson wrote in a June 2023 court filing that such a defense does not comport with standing legal precedents. Kohberger’s DNA was discovered on a leather sheath for a combat-style knife found at the crime scene, according to police and prosecutors. Because that evidence was abandoned, Kohberger cannot assert it is protected, nor can he claim a privacy issue from the use of his relatives’ DNA in the IGG process to develop a family tree, Thompson said.

“Defendant cannot show that he had a reasonable expectation of privacy in DNA left at the scene of a quadruple homicide or in the genetic information of his relatives, who voluntarily provided their own DNA to a genetic genealogy service,” read the court filing.

Attorney David Gurney is a national IGG expert, and director of Ramapo College of New Jersey’s IGG Center. He said that he expected the defense in the Kohberger case would raise a Fourth Amendment challenge — and that such an argument is almost certain to fail.

“There is no Fourth Amendment violation in the use of IGG,” Gurney said Monday in an email to the Idaho Statesman. “Every court that has heard challenges to the use of abandoned DNA by law enforcement has rejected them. The use of crime-scene DNA does not even constitute a search, so the Fourth Amendment is not implicated.”

The prior judge in the Kohberger case also appeared skeptical about a constitutional rights defense against the use of IGG, but after an eight-month battle awarded Kohberger’s attorneys at least some of those records in the case. At the defense’s urging, the trial was later moved from Moscow to Boise and Hippler took over as judge.

The prosecution said the FBI used one or more public ancestry websites during the investigation, but has not revealed which ones. Law enforcement does not have access to the databases from services 23andMe and Ancestry.com, and primarily works with two lesser-known companies called FamilyTreeDNA and GEDmatch — both of which were used to solve the Golden State Killer cold case. Another genealogy website, MyHeritage, also helped identify the suspect in California, according to Gurney.

“Whether they used GEDmatch, FamilyTreeDNA, MyHeritage — or any combination — makes no difference to the Fourth Amendment analysis,” Gurney said of the Kohberger case.

After the FBI’s IGG results settled on Kohberger, agents then sent Idaho police a “tip” to investigate him as the suspect, Thompson said. Traditional investigative techniques were then employed by detectives to build their case against Kohberger and eventually obtain an arrest warrant based on probable cause, the prosecutor said.

“The IGG process pointed law enforcement toward (the) defendant,” Thompson wrote “but it did not provide law enforcement with substantive evidence of guilt.”

Once Kohberger was arrested, police swabbed his mouth and received a “statistical match” in a comparison with the DNA lifted off the knife sheath discovered at the crime scene, Thompson said. The state would plan to present that evidence at trial, he said — not anything to do with IGG, which proponents have called nothing more than another crime-solving technique increasingly used by police in active investigations.

It is unclear whether the arguments over suppressing the IGG evidence will take place at the public hearing later this week. Hippler is expected to rule on the issue in advance of Thursday’s hearing, which is set to start at 9 a.m. If needed, the evidence suppression hearing would extend to Friday, also starting at 9 a.m.

The public hearing is available to watch live on the Idaho 4th Judicial District Court’s YouTube page.

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