Alton Nolen
Alton Alexander Nolen, 31, is seen in a picture from the Oklahoma Department of Corrections taken October 18, 2011. Police said Nolen had been fired from the Vaughan Foods processing plant in a suburb of Oklahoma City September 25, 2014 before he entered a front office and attacked two women. Police said he stabbed 54-year-old Colleen Hufford and severed her head and then stabbed 43-year-old Traci Johnson. The company's chief operating officer, Mark Vaughan, who is also a reserve sheriff's deputy, was the first on the scene and stopped the attack by shooting Nolen. NOTE: MUGSHOT IS FROM A PREVIOUS ARREST REUTERS/Oklahoma Department of Corrections/Handout via Reuters

A 31-year-old Oklahoma man accused of beheading his coworker wants to be executed and refuses to help his attorneys with his defence, a psychologist testified on 26 October. The psychologist, Dr Anita Russell, testified during a competency trial to determine if Alton Nolen is mentally competent to stand trial in the first-degree murder of 54-year-old Colleen Hufford.

Nolen was arrested in September 2014 after allegedly attacking Huffed with a knife and beheading her at Vaughan Foods in Moore, Oklahoma. According to Reuters, the man is also charged with assault and battery with a deadly weapon for attacking a second coworker, 43-year-old Traci Johnson, who survived.

The suspect pleaded not guilty to both charges and no motive has been reveal for the attack, Reuters reported. Nolen is also being investigated by the FBI, which is looking into any potential religious ties to the beheading after his former colleagues claimed he attempted to convert them to Islam.

Russell reportedly told the Oklahoma court that she believed Nolen is incompetent and suffers from mild mental retardation. The psychologist also interviewed Nolen's sister Paige, who said her brother could not establish goals and had trouble in school, News9 reported. His school records reveal he was in special education classes and received low grades. Nolen also underwent an IQ screening, which revealed an overall IQ score of 69.

According to News9, Russell recommended sending Nolen to the Oklahoma Forensic Centre to receive competency classes. She added that she does not believe he is dangerous.

Cleveland County District Judge Lori Walkley said she would not set a trial date until Nolen's mental capacity is determined. His competency trial could take up to three days, according to Reuters. Nolen's defence attorney also told the courts that he has refused to help them prepare his defence and that he should not stand trial.

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