Moscow, ID – The suspect accused of murdering four University of Idaho students last year has alleged investigators planted his DNA on the knife sheath found next to one of the slaughtered victims.

Brian Kohberger, 28, faces a potential death penalty if he is convicted of the Nov. 13, 2022 murders of 21-year-old Kaylee Goncalves, 21-year-old Madison Mogen, 20-year-old Xana Kernodle, and 20-year-old Ethan Chapin.

Kohberger’s defense team said in a filing in June that his DNA could have been planted at the scene at any point during the investigation into the gruesome quadruple homicide, ABC News reported.

They noted that “hundreds of members of law enforcement” worked the case, as well as “at least one lab the State refuses to name.”

The defense team further alleged the Investigative Genetic Genealogy (IGG) methods investigators utilized to link Kohberger to the scene was “like a lineup where the government was already aware of who they wanted to target,” ABC News reported.

They argued the DNA belonging to three other males that was found inside and around the home where the students were murdered was ignored by police and further accused investigators of hiding information regarding how they honed in on Kohberger’s vehicle.

“The Defense is to guess whether the State focused its investigation on Mr. Kohberger via a bizarrely complex DNA tree experiment or through its faulty identification of the vehicle involved in this case,” their filing read.

Prosecutors refuted the defense team’s allegations in a filing on July 17, ABC News reported.

Prosecutors said a commonly-used method of DNA criminal profiling known as short tandem repeat analysis (STR) was initially used in comparison with the DNA left at the crime scene, but that there was no match.

Investigators then took the same DNA profile for the IGG analysis to help guide them in the right direction and generate leads in tracking down the killer, ABC News reported.

Prosecutors said the analysis is entirely separate from the STR DNA profile, which they said they’ve already provided to the defense team.

They said they also have no intention of using the IGG information at trial, but noted the STR analysis is “substantive evidence” prosecutors intend to use “to prove its accusations,” ABC News reported.

“The State is at a loss as to how that theory supports a claim that the lGG information is material to the preparation of his defense,” the Latah County Prosecutor’s Office said in the filing. “If Defendant wishes to explore the theory that his DNA was planted on the Ka-Bar knife sheath, he is free to do so. But the family tree created by the FBI has no relevance to that theory.”

“The IGG information is neither exculpatory nor material to guilt or punishment,” prosecutors added. “The family tree built by the FBI merely pointed law enforcement to Defendant, and law enforcement followed that lead to develop the substantive evidence of guilt that was used for his arrest and that will be used at trial.”

Kohberger is facing four counts of first-degree murder and one count of felony burglary in connection with the stabbing deaths of the four students inside their off-campus residence in Moscow.

He was living and attending school in nearby Washington state at the time of the killings.

Investigators honed in on Kohberger during a six-week hunt using cell phone data, the DNA left at the scene, and by tracking the whereabouts of his white Hyundai Elantra, ABC News reported.

Kohberger has been incarcerated without bail since his apprehension at his parents’ home in Monroe County, Pennsylvania, in December of 2022.

His trial is slated to begin on Oct. 2.