Background: The Dunklin County Justice Center in Kennett, Missouri (Google Maps). Inset: Trevor Huber (Dunklin County Sheriff's Office).

A man's fate has been sealed for killing and decapitating his mother in Missouri because he believed she was trying to poison him — before calling 911 and admitting to the crime.

Trevor Huber, 43, was sentenced to life in prison without the possibility of parole, according to court records reviewed by Law&Crime. He was previously convicted after a bench trial of first-degree murder in the death of 63-year-old Charlotte Wilson.

On Dec. 21, 2018, the mother and son were at a home on North Main Street in Cardwell, Missouri, a small city in the far south of the state along the Arkansas border. According to court records, Huber struck his mother on the head five to seven times with a blunt object.

She was reportedly already dead when he used a knife to decapitate her. After that, he called law enforcement.

According to Jonesboro, Arkansas, ABC and NBC affiliate KAIT, the Dunklin County Sheriff's Office got a call from a man who sounded confused. Officers responded to the home, and Huber answered the door naked.

Huber "did not flee the scene, he did not attempt to move the body, he did not clean up the crime scene, and he did not hide evidence," court records filed by his defense attorney state. "In fact, the bloody knife and slag hammer were left in plain view, covered in blood, on the kitchen table."

Upon finding Wilson's body, investigators arrested Huber, advised him of his rights, and interviewed him. He reportedly "was concerned he killed his mother" and said he believed she was trying to kill him with poison.

According to court records from the defense, a forensic psychologist "testified that Mr. Huber exhibited evidence of methamphetamine-induced psychosis" and also diagnosed him with delusional disorder, though she could not say whether both contributed to the crime.

Huber's interview with investigators contained more important elements. He is said to have written "I killed my mother" on a piece of paper before tearing it up and swallowing it.