Michael Keith Spell, 24, was charged with the attempted kidnapping and murder of Sherry Arnold, a 43-year-old high school teacher who was found in a shallow grave. On January 2012, Arnold never came back from her morning jog. Her body was discovered two months after her disappearance.

On Monday, the defense testified that Spell is not fit for trial, as he is suffering from a mental condition wherein he tends to twist the past. They also said that he has the intelligence of an 11-year-old child, and will not be able to comprehend the case brought against him.

However, testimonies from doctors at the Montana State Hospital said that Spell was only “pretending” not to understand questions during his mental fitness evaluation.

Judge Richard Simonton will have to decide if the defense claims hold true.

Co-defendant  Lester Vann Waters Jr. has already pleaded guilty to the charges in exchange for a plea deal. Prosecutors dismissed the attempted kidnapping charge and instead will push for a 100-year prison sentence, instead of the death penalty. This, however, may result in the death sentence for Spell, if he is convicted. On the other hand, if he is able to avoid trial due to his supposed mental condition, he will be avoiding the death sentence and will instead be housed in a state institution.

Greg Olley, a clinical professor and psychologist, is testifying for the defense. He said that he has already interviewed Spell two times and according to those interviews, he found that Spell is “mentally retarded,” as he was capable of answering routine questions, but failed to answer fundamental ones. Olley also stated that Spell is not a smart person, and that he has a bad memory that is not capable of retaining a lot of information.

Prosecutors say that Olley’s testimony should not be taken into consideration, as there was no written report submitted.

Craig Beaver, a neuropsychologist based in Idaho also testified that Spell’s condition can be proven to exist since he was 5 years old.

Spell’s competency is more difficult to determine, as his case is not severe. Spell has functioned in society, fathering a child and even having worked at different jobs. However, his representatives say that he always scored below 75 on various IQ tests.

Sherry Arnold went for a jog and never returned home

Image via Denver Channel, Twitter