(NewsNation) — The latest court document dump in the Idaho college killings case suggests defendant Bryan Kohberger bought a black face covering 11 months before he allegedly murdered four students as they slept.
Prosecutors say records show Kohberger purchased a black balaclava Jan. 10, 2022, at a Dick’s Sporting Goods while he was in Pittsburgh. The deaths of Kaylee Goncalves, Madison Mogen, Xana Kernodle and Ethan Chapin happened Nov. 13 in Moscow, Idaho.
State prosecutors have previously disclosed they have online shopping records indicating Kohberger bought the murder weapon — a combat-style knife — as well as a sheath and sharpener eight months before the killings. A sheath with DNA linked to Kohberger was found at the crime scene.
Introducing information about the face covering could bolster the account of a surviving roommate who told police she saw a bushy-eyed stranger in the house who was wearing a black mask.
Bryan Kohberger charged with first-degree murder
Kohberger was a graduate student at Washington State University in nearby Pullman, Washington. He has been charged with first-degree murder, has pleaded not guilty, and is expected to go to trial in August.
Prosecutors say he drove the type of white Hyundai Elantra that was seen in the area during the time of the killings.
Smiling selfie of Bryan Kohberger disclosed earlier
Previous court documents also showed a selfie that Kohberger is said to have taken the morning of Nov. 13, 2022, hours after the killings. In the picture, Kohberger is seen smiling and giving a thumbs-up, possibly in front of a tiled shower.
Newly released court documents include this smiling selfie of Bryan Kohberger, allegedly taken on the morning four University of Idaho students were killed. 
FILE – Bryan Kohberger, accused of fatally stabbing four University of Idaho students, is escorted into court for a hearing in Latah County District Court, Sept. 13, 2023, in Moscow, Idaho. (AP Photo/Ted S. Warren, File) 
Bryan Kohberger, left, who is accused of killing four University of Idaho students in November 2022, appears at a hearing in Latah County District Court, Thursday, Jan. 5, 2023, in Moscow, Idaho. (AP Photo/Ted S. Warren, Pool) 
MOSCOW, IDAHO – JUNE 27: Bryan Kohberger enters the courtroom for a hearing at the Latah County Courthouse on June 27, 2023 in Moscow, Idaho. Kohberger is accused of killing four University of Idaho students in November 2022. (Photo by August Frank-Pool/Getty Images) 
FILE – Bryan Kohberger, left, who is accused of killing four University of Idaho students in November 2022, looks toward his attorney, public defender Anne Taylor, right, during a hearing in Latah County District Court, Jan. 5, 2023, in Moscow, Idaho. Law enforcement officials seized dark clothing, medical gloves, a flashlight and other items from a Pennsylvania home where they arrested Kohberger, a graduate student charged with stabbing four University of Idaho students to death, according to newly unsealed court documents. The records were made public Tuesday, Feb. 28. (AP Photo/Ted S. Warren, Pool, File) 
Bryan Kohberger, facing first-degree murder charges in the deaths of four University of Idaho students last fall, is seen at the Monroe County Courthouse in Pennsylvania on Tuesday, Jan. 3, 2023. 
Bryan Kohberger, who is accused of killing four University of Idaho students, is escorted to an extradition hearing at the Monroe County Courthouse in Stroudsburg, Pa., Tuesday, Jan. 3, 2023. (AP Photo/Matt Rourke, Pool) 
UNDATED – PENNSYLVANIA: (EDITORS NOTE: Best quality available) In this handout provided by Monroe County Correctional Facility, 28-year-old Bryan Christopher Kohberger is seen in a booking photo after he was arrested on December 30, 2022 in Pennsylvania. Kohberger has been accused of fatally stabbing four University of Idaho students – Ethan Chapin, 20, Xana Kernodle, 20, Madison Mogen, 21, and Kaylee Goncalves, 21 – in an off-campus house on November 13, 2022 in Moscow, Idaho. (Photo by Monroe County Correctional Facility via Getty Images)
Prosecutors have indicated they would like to use the photo of Kohberger to show jurors he has the type of eyebrows described by the roommate.
When is Bryan Kohberger’s trial?
Kohberger’s trial is set for August 11, 2025. A judge ruled in November 2024 that he is able to face the death penalty.
Defense attorneys asked a judge previously to dismiss most of the evidence in Kohberger’s case as they said it relies on a genetic investigation process they called unconstitutional. During a January hearing, Kohberger’s lawyers argued that the search warrants obtained were tainted by police conduct.