Disturbing new details have emerged about Bryan Kohberger's meticulous planning ahead of his crimes - and his efforts to then evade capture following the murders of four University of Idaho students.

Newly unsealed court records reviewed by the Daily Mail show how the criminology PhD student shopped for a 'fighting knife' on Amazon, selecting an $86 military blade as his weapon of choice months before the quadruple homicide.

The filings also show how, in the days leading up to the murders and in the weeks that followed, Kohberger drastically changed his normal spending habits.

He ditched his debit card and used only cash - withdrawing it from a bank account he had never before used.

Kohberger's Amazon purchase and bizarre shifts in behavior were previously known to some extent.

But the new filings, unsealed by Ada County Court this week, shine a more forensic light on his actions for the first time - and raise fresh questions about when exactly he formulated his plan to kill, the extent of his organization and when he landed on November 13, 2022, as the day his sick plot would come to fruition.

It was back in March 21, 2022, when the then-27-year-old spent $86.15 on what was described on Amazon as a 'KA-BAR Full Size US Marine Corps Fighting Knife, Straight' and another $23.40 on a 'KA-BAR 9926 Sharpener' from the online marketplace, the records show.

Kohberger's Amazon account had been active since 2017 but, in what appears to be an attempt to create a degree of separation to the purchase he was about to make, he had bought a $130 digital Amazon gift card on the night of March 20. 

That day, he had been browsing various Ka-Bar style knives on Amazon.

Just after midnight on March 21, he made his pick and used the gift card to buy the knife and sharpener for a combined total of $109.55.

The order was to be shipped to Kohberger at his parents' home in Albrightsville, Pennsylvania, where he lived at the time before moving across the country to enroll at Washington State University in Pullman, Washington, that July.

Later that afternoon, the strict vegan then decided to use the remaining balance on the gift card to buy himself some vegan dietary supplements, 'Omega Vegan DHA Supplements Garden of Life,' for $44.78. The gift card covered $20.45 of the purchase, with Kohberger paying for the remaining $24.33 on his visa card.

Over the coming days, Kohberger eagerly awaited the delivery of his murder weapon, repeatedly checking its shipping progress daily from March 22 to 27.

Eight months later, in the early hours of November 13, 2022, he broke into an off-campus college home in Moscow, Idaho, and used that same knife to murder Madison Mogen, Kaylee Goncalves, Xana Kernodle and Ethan Chapin.

During the frenzied attack, Kohberger left his knife sheath behind at the scene. This was a crucial piece of evidence that proved he was the killer: DNA on the clasp was found to be a match through Investigative Genetic Genealogy.

The murder weapon - which was used to stab the four victims more than 150 times in total in around 15 minutes - has never been found.

Searches of his student apartment in Pullman, his student office at WSU, his white Hyundai Elantra car and his parents' home failed to uncover the knife.

There is some speculation that he disposed of the knife on the day of the murders - when he took a long drive to Clarkston, Washington, close to the vast Snake River.

Wherever the knife ended up, only Kohberger currently knows.

But, with his knife and sheath gone after the murders, the killer soon began shopping for replacements, the records show.

First, on November 15, 2022 - three days on from the slayings - Kohberger 'navigated to a page related to the deletion of account activity.'

Then on both November 23 and December 6, he viewed pages associated with Ka-Bar style knives with sheaths on Amazon.

As well as his forward-planning, the newly-released court records offer a glimpse into the lengths Kohberger went to to try to get away with murder.

In the few days leading up to the murders and his final six weeks as a free man afterwards, Kohberger drastically changed his normal spending habits, the state's expert analysis of his spending habits, debit card purchases, and ATM withdrawals reveals. 

In that time, the mass killer shifted from being a habitual user of his debit card to solely withdrawing cash from a different bank account altogether.

Both in Pennsylvania and Washington, Kohberger had largely used his PSECU debit card to make purchases.

Between January 1 and November 30, he withdrew no cash from the PSECU account, instead using it to make purchases including at stores in Moscow in the run-up to the murders.

He used the card on November 10 - three days before the murders - when he shopped at Target and Marshalls in Moscow. Then, he never used his card again.

That August - one month after moving to Washington - Kohberger had opened a new WTB bank account with a deposit of $50.

Four days later, on August 30, $2,000 was deposited into the account.

Then, it sat dormant - with Kohberger not using the account or the money at all.

That all changed on the day of the murders.

At 10.49am on November 13 - six hours after he killed the four students and around an hour before their bodies were discovered - Kohberger made his first ATM withdrawal from the account.

After that, he made seven further ATM cash withdrawals from the account before his arrest. His PSECU debit card remained inactive.

It is unclear if the second account was created in August for the purpose of avoiding detection, but Kohberger's actions both before and after the murders point to the extent of his premeditation. 

Investigators have previously revealed other ways in which Kohberger changed his habits following the murders. He started wearing gloves everywhere and changed his license plates on his car from Pennsylvania to Washington state plates.

But, despite those efforts, the criminology student could not get away with his crimes.  

He was arrested in a dawn raid on his parents' home on December 30, 2022, and charged with the four murders. 

After fighting the charges for more than two years, he finally pleaded guilty in July 2025 as part of a plea deal that would hand him life without parole but spare him from the death penalty.

To this day, no connection has ever been found between him and any of his victims or their two surviving roommates.

And when exactly he decided he was going to kill - and why - remains a mystery.

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