SIDNEY, Mont. (AP) – Sharply divergent images of a Colorado man charged with killing a Montana teacher during a random abduction attempt emerged during a hearing Tuesday to determine whether the suspect is fit for trial.

The prosecution cast 24-year-old Michael Keith Spell as a manipulative if mentally challenged conniver, eager to reduce his punishment by playing up his intellectual disability.

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Defense experts described Spell as easily confused and prone to forget even basic facts within minutes. They said that leaves him unable to meaningfully participate in the complex murder case he faces for the alleged killing of 43-year-old Sidney High School math teacher Sherry Arnold in January 2012.

Montana District Judge Richard Simonton is now tasked with deciding if Spell is fit for trial. After two days of testimony ended Tuesday, Simonton said he would make his decision “as soon as possible” but offered no hint on how he might rule.

Spell waived his right to be present for the hearing.

If he stands trial, he could face the death sentence.

But if he is ruled incompetent, felony charges of deliberate homicide and attempted kidnapping could be dismissed and Spell would be committed to a state institution with the potential for eventual release.

Accomplice Lester Van Waters Jr. – implicated by Spell as the killer – pleaded guilty in a deal with prosecutors that calls for him to testify against Spell. Under that deal, Van Waters, 50, would escape a death sentence.

State psychiatrist Virginia Hill said during more than five hours of testimony Tuesday that she believes Spell is competent despite his low scores on mental-fitness tests during a two-month evaluation at Montana State Hospital.

Spell played video games, did his own laundry and manipulated other patients during his stay at the hospital in Warm Springs, Hill said. Spell showed himself to be “relentless” in his pursuit of personal goals, whether those were more privileges at the hospital or minimizing the consequences of his alleged crime, she said.

“Tests are not X-rays. Tests are not infallible,” Hill said. “He’s just a survivor who will do what he needs to do to get his end result.”

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Defense attorney Al Avignone attempted to poke holes in Hill’s testimony by pointing out that Spell’s supposed manipulations of other patients in most cases involved trying to convince them to give him potato chips and other snacks. He also chided prosecutors and Hill for allegedly submitting “cherry-picked” information about Spell that ignored evidence of his incompetence.

The case has unfolded against a backdrop of spiking crime rates in eastern Montana and neighboring parts of North Dakota, where an oil boom has transformed once-quiet agricultural communities. The killing of Arnold – a Sidney High School math teacher widely beloved in the community – stood out for its violent, random nature.

Court documents, including law-enforcement affidavits and testimony from Spell’s accomplice, say the defendants arrived in Montana after a drug-fueled drive from Parachute, Colo., and spotted Arnold jogging along a Sidney street. Arnold died after Spell choked or otherwise asphyxiated her during an attempted abduction, according to prosecutors.

In testimony put up by the defense earlier in the week, Craig Beaver, a Boise, Idaho-based neuropsychologist, said Spell was prone to distort past events. Beaver said he documented evidence of Spell’s mental shortcomings dating to when the defendant was just 5 years old, which Beaver said undercut claims that the defendant was exaggerating his mental condition to avoid trial.

“Everyone that has evaluated Mr. Michael Spell, up until the Montana State Hospital, has found that he had intellectual limitations,” Beaver said.

Previously, Spell was declared incompetent to proceed by courts in Colorado during a 2010 drug case and a 2007 case when he was a juvenile.

His attorneys say there is no conclusive evidence Spell was the one who killed Arnold. They have not denied his involvement in the events leading up to her death.

Spell told FBI agents that he grabbed Arnold and dragged her back the co-defendant’s vehicle before Van Waters climbed into the back seat and choked her, according to court documents.

– By MATTHEW BROWN, Associated Press

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