In a new filing, the prosecution argued the judge should limit the evidence Kohberger's attorneys can present to support his alibi for the November 2022 murders of Kaylee Goncalves, Madison Mogen, Xana Kernodle and Ethan Chapin.
Kaylee Goncalves, Ethan Chapin, Xana Kernodle and Madison Mogen were killed in the attack.
Obtained by CNN via CNN Newsource
Kohberger, a Washington State University graduate student in criminology, was arrested in the killings on December 30, 2022, in his home state of Pennsylvania. He was charged with four counts of murder; a not-guilty plea was entered on his behalf in May 2023, and his attorneys have indicated the 29-year-old intends to present an alibi as part of his defense.
Kohberger's attorneys, who say their client is innocent, have alleged that he was driving alone, stargazing the night the four University of Idaho students were stabbed to death in an off-campus home.
But as the August trial approaches, prosecutors are asking a judge to bar Kohberger's defense team from offering any evidence -- beyond Kohberger's own words -- to support that claim, saying the defense has had 20 months to provide material to back it up and has not.
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"The defense is making the argument that Bryan Kohberger was out for a drive in no specific area or place. And that's his alibi. And they presented no witness to be able to testify to that. So, the prosecution is arguing that if the defense does raise any argument about alibi, that would have to come from Bryan Kohberger and no other source," explained ABC News legal contributor Brian Buckmire.
The prosecution is also requesting to ban the defense team from offering any psychiatric evaluations into evidence. This, after summaries of court documents in the case show the defense filed a motion Monday "to Strike Death Penalty RE: Autism Spectrum Disorder."
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As of early Wednesday morning, the full documents were not publicly available online. And it was not immediately clear whether Kohberger has been diagnosed with autism spectrum disorder or if the defense was seeking a diagnosis, CNN reported.
Prosecutors also asking the court to bar references to "alternative" culprits unless they have "evidence specifically connecting [them] to the homicides."
CNN contributed to this report.