A man who beheaded his stepmother in 2005 has finally been ruled competent to stand trial, but experts on both sides of the case agree that he was mentally ill at the time of the killing, raising the probability of a successful insanity finding.

A Dakota County judge on Friday found Stephen R. Miles, 27, competent to finally stand trial for second-degree murder.

After a brief trial conducted with facts agreed on by both sides, Dakota County Judge Kathryn Messerich said she'll rule in one week whether Miles is guilty or not in the killing of Maris Jo Miles.

The case is unusual not only for its gruesomeness, but also for its rare invocation of the McNaughton rule, the famous legal standard that determines whether a person can be found not guilty of a crime by reason of mental illness. Marsh Halberg, Miles' attorney, said he knows of only one case in which the McNaughton defense was used in Dakota County.

Doctors from both the prosecution and defense agreed that Miles was mentally ill when he decapitated Maris Miles in her home while his father was outside shoveling snow.

Halberg said that if the judge agrees with the doctors that Miles is not guilty by reason of mental illness, she could continue to keep him civilly committed to the care of the Minnesota Security Hospital in St. Peter.

After court in Hastings on Friday, deputies returned Miles to the hospital.

"This a classic case of someone who should meet McNaughton standards," Halberg said.

Both sides had agreed on the facts -- that Miles killed his mother and that he was insane at the time. The brief trial relied largely on papers given to the judge and Stephen Miles' brief responses to questions.

He had waived his right to a jury trial.

"We've never said he didn't cause the death," Halberg said afterward. "The whole issue is what's the best remedy for him: Should he be incarcerated or put into a mental health care facility? That's what this has always been about and that's what his parents' concern has always been."

Attempts to get help

Shortly after Miles was arrested, attention focused on the family's unsuccessful attempts to hospitalize him just hours before the killing. He had been diagnosed the year before as having disorders, including schizophrenia.

His parents, Roland and Carol Miles, had struggled for years to get help for their son, especially in the months before Maris Miles died. Stephen Miles had refused to take antipsychotic medications.

Burnsville police were called to the family's house on Country View Court just before 9:30 p.m. on Dec. 30, 2005. They found Stephen Miles, covered in blood, sitting on a patio bench next to his father. In the kitchen, officers found the decapitated woman.

At the police station, Stephen Miles told a detective that he had "wanted help for his head" that day. Later in the day, his stepmother had become upset with him and his father. Miles confessed that he got a hatchet from his father's garage, went to the kitchen, hit his stepmother on the top of the head with the blade, and used a knife to cut off her head.

Halberg said that after four years of treatment and medication, Miles understands what he did. His parents stood by him while his case remained in limbo for four years.

"The parents visit him every week and have been extremely supportive of him trying to get well," Halberg said. "There's obviously heartache. This is a gruesome death that occurred and no one's minimized that. They recognize the tragedy for everyone involved, and the ripple effect on others, but their unconditional love for their child remains."

Joy Powell • 952-882-9017