Recently, new photographs have surfaced, showcasing the pivotal piece of evidence that exposed Bryan Kohberger as the perpetrator behind the tragic slaying of four University of Idaho students.

In his hurried escape during the early hours of November 13, 2022, Kohberger inadvertently left behind a brown leather Ka-Bar knife sheath. This crucial misstep occurred after he brutally attacked and murdered Kaylee Goncalves, Madison Mogen, Xana Kernodle, and Ethan Chapin.

The abandoned sheath became the linchpin in solving the case, as forensic genetic genealogy linked DNA found on it to Kohberger, a 30-year-old criminology PhD student. The DNA evidence, discovered at the crime scene on King Road in Moscow, Idaho, played a vital role in pinpointing Kohberger as the suspect.

In a recent release of over 2,300 pages of evidence by law enforcement, photos of the knife sheath have been unveiled for the first time. These images depict the sheath’s brown leather form, emblazoned with a USMC military seal, and measuring just under 15 inches in length.

Investigations revealed that Kohberger had purchased the sheath along with a Ka-Bar knife, believed to be the murder weapon, from Amazon in March 2022. This was eight months prior to the killings and three months before his relocation from Albrightsville, Pennsylvania, to Pullman, Washington.

Kohberger bought the sheath and a Ka-Bar knife believed to be the murder weapon from Amazon in March 2022 – eight months before the murders and three months before he moved from his parents’ home in Albrightsville, Pennsylvania, across the country to Pullman, Washington.

The knife has never been found.

Photos have been revealed for the first time of the key piece of evidence (pictured) that led to Bryan Kohberger being unmasked as the murderer of four University of Idaho students

Kohberger left this brown leather Ka-Bar knife sheath behind at the scene of the murders at 1122 King Road in Moscow, Idaho

Bryan Kohberger at his sentencing in Ada County Courthouse in Boise, Idaho, on July 23 

During the November 13, 2022, attack, Kohberger mistakenly left the sheath next to Mogen’s body in her bed on the third story of the home.

The newly released documents, which largely pertain to the DNA and forensic testing conducted in the case, include text messages between investigators where they reveal the sheath was initially checked for fingerprints but that no prints were found.

Idaho State Police Forensic Services reports reveal that swabs were taken from the front strap, edges on the handle portion of the sheath, edges on the blade portion and stains on the back, for forensic testing.

Blood belonging to best friends Mogen and Goncalves, who were both killed in Mogen’s bed, was found on the back of the sheath, the documents reveal.

A DNA profile from a then-unidentified male was found on the clasp.

It was entered into CODIS – the law enforcement database of known offenders – but there was no match, meaning the perpetrator did not appear to have committed any past crimes.

With no match in CODIS, the DNA sample was sent to Othram’s forensic genetic genealogy lab in Texas where the team built a DNA profile of the killer.

Within 48 hours, the team determined the assailant’s ancestry went back multiple generations in the US, and that his family derived from Pennsylvania, and had a very specific Italian background.

Young couple Ethan Chapin and Xana Kernodle were murdered by Bryan Kohberger on November 13, 2022

Kaylee Goncalves and Madison Mogen pictured together. Kohberger left behind the knife sheath in the bed where the two best friends’ bodies were found

Othram found that only two families in the whole of America fit that specific criteria. 

And among those families, there was only one man who could have been in Moscow on the day of the murders.

Kohberger drove a white Hyundai Elantra matching the suspect’s vehicle and lived just ten minutes from the victims, over the state border in Pullman.

After the suspect was identified, law enforcement officers tracked him down to his parents’ home in Pennsylvania and posed as garbage collectors to do a trash pull to try to obtain a DNA sample.

Among the newly released ISP photos and lab reports are the trash collected from Kohberger’s parents’ home including band aids, a straw, pink earplugs, lollipop sticks, water bottles, a Dunkin’ Donut coffee cup and nail clippers.

Also among the trash was the Q-tip that investigators were able to determine contained DNA from the father of the person whose DNA was on the sheath.

Once this came back a match, Kohberger was arrested for the murders.

The ISP documents also reveal other evidence collected and sent to the Idaho State Crime Lab as part of the investigation, including fingernail clippings from the victims, swabs of blood from the murder scene, swabs from the back sliding door that the killer used to gain entry to the home and prints taken from the handprints left on the kitchen window.

Forensic genetic genealogy was used to trace DNA on the sheath to the 30-year-old criminology PhD student

The brown leather sheath features a USMC military seal and measures less than 15 inches long

Search warrants also show what investigators hoped they might find inside Kohberger’s apartment and office in Pullman including any evidence connecting him to the four victims.

Ultimately, investigators found no connection between Kohberger and any of the victims and his motive remains a mystery.

Kohberger’s Hyundai Elantra – which he used to drive to and from the crime – was also forensically tested, with documents revealing a cutting from the bottom seat cushion, the seat belt boot, a floor mat and gear shift knob were removed for analysis.

Following Kohberger’s sentencing, Latah County Prosecutor Bill Thompson told reporters the killer had ‘meticulously cleaned’ his car leaving no evidence behind.

Documents from the investigation have been trickling out ever since Kohberger was sentenced to life in prison in July. 

The mass killer fought the charges for more than two years before he struck a controversial plea deal weeks before his trial was set to begin.

Under the terms of the deal, Kohberger avoided the death penalty and was sentenced to life in prison with no possibility of parole. He also waived all rights to appeal. 

At his sentencing on July 23, Kohberger refused the opportunity to speak and reveal any details or motive for his crimes. 

He is serving his sentence inside Idaho’s maximum security prison in Kuna where he has already filed multiple complaints about his fellow inmates. 

While behind bars, Kohberger is continuing to fight the families of his victims over restitution payments.

In a court filing last month, his legal team argued he should not have to pay extra money requested by prosecutors on behalf of the families of Mogen and Goncalves because they received money from the public through GoFundMe campaigns.

The defense also argued Kohberger has no way to pay because he is in prison.

The prosecution has since pushed back, pointing out that Kohberger has been receiving money from his family members – as well as strangers – while behind bars.

A hearing on the matter is scheduled for November 5.