By Rebekah Riess, CNN
(CNN) — A recently unsealed defense motion in the capital murder case against Bryan Kohberger offers the most detailed picture of the suspect’s personality to emerge since his arrest in the brutal killings of four University of Idaho students.
Attorneys for Kohberger claim in the motion the 30-year-old has autism spectrum disorder – or ASD – and executing him would violate the Eighth Amendment’s prohibition on “cruel and unusual punishment.”
Kohberger displays “extremely rigid thinking, perseverates on specific topics, processes information on a piece-meal basis, struggles to plan ahead” and “demonstrates little insight into his own behaviors and emotions,” the filing notes, citing a medical evaluation commissioned by his attorneys.
“Due to his ASD, Mr. Kohberger simply cannot comport himself in a manner that aligns with societal expectations of normalcy. This creates an unconscionable risk that he will be executed because of his disability rather than his culpability,” his attorneys said.
Prosecutors have said they will seek the death penalty at his trial – scheduled for August.
Kohberger is accused of killing Madison Mogen, Kaylee Goncalves, Xana Kernodle and Ethan Chapin at an off-campus home in November 2022. Not guilty pleas have been entered on his behalf.
The newly unsealed filing is the latest in a flurry of defense motions aimed at taking the death penalty off the table for the only suspect in the fatal stabbings that horrified the small college community of Moscow. The investigation culminated with the arrest in Pennsylvania of Kohberger, a criminology graduate student.
The US Supreme Court has declined to hear previous arguments by capital defendants seeking to use some developmental disorders, including autism spectrum disorder, to argue against the death penalty, a legal expert told CNN.
What the new filing says about Kohberger
It’s unclear if – or when – Kohberger was previously diagnosed with ASD, but the new filing cites an evaluation by a neuropsychologist, who found Kohberger “continues to exhibit all the core diagnostic features of ASD currently, with significant impact on his daily life.”
The neuropsychologist, hired by his defense, wrote in her evaluation of Kohberger that he displayed deficits in social-emotional reciprocity and “impulsive tendencies,” including “compulsions around hand-washing and other cleaning behaviors,” the filing says.
In the filing, attorneys for Kohberger describe him as a “highly distractable” man with an “intense gaze” who “demonstrates little insight into his own behaviors and emotions,” citing the medical evaluation performed by Dr. Rachel Orr.
Previous Supreme Court rulings have determined youth and intellectual disability “create an unacceptable risk of wrongful execution because they hamper the defendant’s ability to present mitigation evidence,” Kohberger’s attorneys said.
Likening ASD to an intellectual disability, they argue such defendants are unable to “make a persuasive showing of mitigation in the face of prosecutorial evidence.”
While the evaluation found that Kohberger possessed strong verbal abilities, “his language was often overinclusive, disorganized, highly repetitive, and overly formal,” and he was “highly distractable,” the filing said.
Kohberger was a graduate student at Washington State University’s Department of Criminal Justice and Criminology and had finished his first semester as a Ph.D. student in the school’s criminal justice program in December 2023, CNN previously reported.
Kohberger “subtly rocks his upper torso, especially while engaged in a cognitive task or listening to someone else,” and “exhibits atypical eye contact, including an intense gaze,” the neuropsychologist observed, according to the filing.
His facial expressions – including a concentrated gaze – “are already being assigned sinister meaning by observers,” Kohberger’s attorneys claim, citing media coverage ahead of the trial. An Idaho judge already agreed to move the trial venue, citing media coverage of the case and concerns that the local community is prejudiced against the suspect.
“A jury in this case will be emotionally overwhelmed by the factual allegations, and simultaneously looking at a defendant who appears to be emotionally uninvested and unmoved and who cannot persuasively testify in his own defense … amounting to an unconstitutional risk that Mr. Kohberger – on account of his disability – will be unreliably convicted and sentenced to death,” the motion states.
Legal duel over death penalty
Kohberger’s lawyers filed a myriad of motions last year listing reasons they believe the state’s intent to seek the death penalty is unconstitutional.
One focused on what Kohberger’s defense team calls an “ideological shift” and “evolving standards” in the way Americans view the death penalty. Other motions argued Idaho’s death penalty statute constitutes a violation of international law and the fundamental precepts of international human rights.
The motion unsealed this week also follows his defense team’s failed attempt to convince a judge to suppress evidence related to investigative genetic genealogy, a relatively new technique authorities use to upload an unknown suspect’s DNA profile to a database in a bid to identify potential relatives.
In a motion filed last Monday, the defense again asked that DNA evidence in the case be kept from the jury in the trial because jurors could believe the DNA gathered by prosecutors is Kohberger’s, and – according to the defense – it is not.
Kohberger’s attorneys, led by Anne Taylor, also point in the new filing to the Supreme Court’s prohibition on the death penalty in cases where a defendant has any characteristic that “renders him less culpable, negates the retributive and deterrent aims of capital punishment, or creates a risk of an erroneous death sentence.” They argue this applies to defendants with autism spectrum disorder.
ASD is a neurological and developmental disorder that can affect how people interact with others, communicate, learn and behave, according to the National Institute of Mental Health.
“People with ASD, including Mr. Kohberger, exhibit deficits in nearly all the same areas cited by the Court in concluding that it is unconstitutional for people with intellectual disabilities to be sentenced to death because such sentences are not proportional and cannot be reliably imposed,” the new motion states.
“A diagnosis of an autism spectrum disorder is as relevant to police and legal proceedings as a diagnosis of mental retardation or mental illness would be, no matter how bright, high functioning, and/or verbal the person may be,” nonprofit advocacy group Autism Speaks said in a resource page on the judicial system.
Likening ASD to an intellectual disability, Kohberger’s attorneys also argue that such defendants are unable to “make a persuasive showing of mitigation in the face of prosecutorial evidence.”
Supreme Court declined to hear previous claims based on autism defense in capital cases
Kohberger’s defense team cites Atkins v. Virginia in the new filing – a case in which the Supreme Court prohibited executions of people with intellectual disabilities, identifying several characteristics making those defendants “categorically less culpable than the average criminal.”
The prohibition includes those having “diminished capacities to understand and process information, to communicate, to abstract from mistakes and learn from experience, to engage in logical reasoning, to control impulses, and to understand the reactions of others.”
But the Supreme Court has declined to review every attempt by capital defendants to extend the reach of Atkins to other developmental disorders, including autism spectrum disorder, Robert Dunham, director of the Death Penalty Policy Project told CNN.
Even if the motion doesn’t succeed in barring the death penalty, Dunham sees “good strategic reasons” why the defense might raise the issue.
“It’s not just because people with severe autism have the same type of adaptive deficits, have the same type of problems functioning in society, that individuals with intellectual disability have. Here, there’s also a reason to raise the issue because Kohberger’s autism is going to affect virtually every aspect of the case,” Dunham said.
“They want the judge to know that his autism impairs their ability to confer with him about strategy. They want the judge to know that jurors will be looking at him and his behavior and making judgments about his likely guilt or innocence, when his demeanor has nothing to do with that – it has everything, instead, to do with some of the off-putting behaviors that go along with autism,” Dunham said.
“They want to educate the judge that, things that should be considered reasons for life, in this case, may be misinterpreted as reasons for death.”
If the court in Idaho accepts Kohberger’s motion as a valid legal argument, prosecutors will have to figure out whether or not he qualifies as having ASD, Austin Sarat, a law professor at Amherst College said.
In an earlier filing, prosecutors cited a state law that stipulates “mental condition shall not be a defense to any charge of criminal conduct,” except when “expert evidence on the issues of any state of mind which is an element of the offense” is introduced.
“Part of the problem in death cases, especially with their allegations about an intellectual disability, is to distinguish a claim that the defendant is not responsible, from a claim that while the defendant is responsible, the conditions under which they acted should mitigate the punishment … and that’s what I think they’re doing in this,” Sarat told CNN.
CNN’s Jean Casarez, Holly Yan, and Jamie Gumbrecht contributed to this reporting.
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