Idaho police pieced together DNA evidence, cellphone data and surveillance video to charge a criminology graduate student with the November slaying of four University of Idaho undergraduates, according to an affidavit unsealed Thursday. The affidavit says DNA matching that of 28-year-old Bryan Kohberger was found on a knife sheath recovered at the crime scene, just a short drive across the state border where he is a criminal justice doctoral student at Washington State University. The affidavit also says that a cellphone belonging to Kohberger was near the victims’ home on a dozen occasions prior to the killings, and that while it was apparently turned off around the time of the early-morning attack, cell tower data place his phone in that region of Idaho shortly afterward.
Kohberger made his first appearance Thursday in an Idaho court, where he faces four charges of first-degree murder.
He did not enter a plea, and was ordered held without bail.
The affidavit details a chilling encounter between one of the victims’ surviving roommates and a masked intruder the night of the stabbings in Moscow, Idaho.
But many questions remain unanswered, including whether Kohberger and any of the victims knew each other, and why police weren’t alerted until nearly eight hours after the killings likely occurred.
READ MORE: Idaho quadruple murder suspect applied to join police before killings
Traces of DNA from a lone male later determined to be Kohberger were found on the button of a leather knife sheath found in the rental home where the victims were killed, according to the affidavit written by Brett Payne, a police corporal in Moscow.
Investigators later closely matched the DNA on the sheath to DNA found in trash taken from Kohberger’s parents’ home in Pennsylvania, where he was arrested last week.
The sheath had a US Marine Corps insignia on it, though there’s no record of Kohberger having served in the military.
The attack that occurred in the early morning hours of an off-campus home had spread fear throughout the university and surrounding area for weeks, as authorities seemed stumped by the brutal stabbings.
The affidavit connects some of the dots between the surveillance footage and cellphone data. Kohberger’s phone pinged communications towers in the region at the same time and in the same areas that the white Elantra was seen driving in the hours after the killings, the affidavit says.
The cellphone data included another chilling detail, the affidavit said: It pinged a cell tower near the victims’ neighborhood hours after the attack, around 9 am.
Latah County prosecutors have said they believe Kohberger broke into the home with the intention of killing the victims: Kaylee Goncalves, 21; Madison Mogen, 21; Xana Kernodle, 20; and Ethan Chapin, 20.
But investigators have made no public statements about a possible motive, or whether any weapons have been found.
Two other housemates were at home during the killings, but were not physically harmed.
