Michael Keith Spell is charged with the attempted kidnapping and murder of 43-year-old Sherry Arnold, who was killed in January, 2012 when she was abducted while jogging near her home in Sidney, MT.

The men that police say kidnapped and killed Arnold — Michael Keith Spell, 24, and Lester Van Waters Jr., 50, both of Parachute, Colo., pleaded not guilty last month to one count each of aggravated kidnapping.

Spell and his legal team are taking the defense tactic that he is not fit for trial because of suspected mental disabilities. A defense expert testified that he is easily confused, and is as intelligent as an 11-year old, which makes him unable to comprehend the case against him.

But, doctors at Montana State Hospital suspect Spell of “pretending” while being questioned, unable to answer questions accurately during an evaluation.

Spell’s co-defendant, Lester Van Waters, Jr. has pleaded guilty. Spell could face the death sentence if convicted.

Defense expert says this Colorado man is not fit for trial in murder of a Montana teacher http://t.co/VvCrhTz8hi pic.twitter.com/eHts6TzqcQ

— 7NEWS Denver Channel (@DenverChannel) March 24, 2014

The search for Arnold went on for nearly three months, but it was Van Waters who led searchers to the shallow grave where Arnold had been buried, outside of Williston, N.D.

Van Waters reached a plea deal that would allow him to avoid a death sentence in exchange for testimony against Spell if the case goes to trial.

Montana murder case suspect seeks to avoid trial – Sherry Arnold #SherryArnold – TBO http://t.co/5lyUPqLsiG

— Missing US news (@MissingUSnews) March 24, 2014

Spell implicated Van Waters as the killer in an FBI interview following his arrest. Van Waters has a lengthy criminal record and spent time in prison more than once in Florida before meeting up with Spell in Colorado.

However, psychologist Greg Olley, a clinical professor at the University of North Carolina School of Medicine, told a Sidney, Mont., courtroom Monday that 24-year-old Michael Keith Spell is unfit for trial in the January 2012 killing of Sherry Arnold.

Olley is claiming that Spell is unable to comprehend the legal issues in this case. “I observed him being really confused most of the time about the questions he was asked, and not being able to provide adequate answers to show he could understand the conversation.”

“He’s not smart,” added Olley, also commenting on his ‘terrible memory’.

Previous court documents show that initially, Spell confessed to the murder and even tried to lead police to the body, claiming that he and his partner Van Waters were on crack cocaine.

Spell told investigators he pulled her into a car and Waters choked her to death before they buried her in a shallow grave on a farmstead near Williston.

If Judge Richard Simonton agrees with the defense claims that Spell is incompetent because of mental disability, he could avoid trial and be sent to a state institution, possibly becoming eligible for eventual release.

Spell’s attorneys have not denied his involvement in Arnold’s death, but hold that there is no “conclusive evidence” that he was the one who killed her.

The Judge has his work cut out for him, because determining competency is difficult when the disability is not severe. Spell has worked many jobs and has a child, however, his IQ is below 75.

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