A judge has acquitted a man in the brutal beating and stabbing death of his 61-year-old mother at their St. Paul home in 2021.

Ramsey County Chief Judge Leonardo Castro found Christopher Aaron Olson, 41, not guilty by reason of mental illness this week in connection with the Nov. 10, 2021, grisly murder of Sonya Olson, who died of blood loss due to stab wounds to the face and traumatic brain injuries.

Olson has struggled with mental illness since at least 2010, his first of several civil commitments for treatment. He began taking medications in his early 20s for bipolar disorder, but would stop taking them, resulting in hospitalizations for manic and psychotic episodes, court records say.

The criminal proceedings were put on hold in March 2022 after Olson was found to be incompetent to stand trial. A month later, after a pre-petition screening, he was civilly committed for an indeterminate period as mentally ill and dangerous. He’s remained confined at a Minnesota Department of Human Services facility since.

Cindy Olson, Sonja Olson’s sister, told the Pioneer Press in 2021 that she was a good woman who believed in God, worked two jobs and would do anything for her children.

She said Olson owned the Payne-Phalen home where she was killed and that two of her sons, Christopher and his twin brother, also lived there. “I feared for Sonja one day that this would happen,” she said. “I told her this, but a mother’s love … is strong.”

‘Off his medications’

St. Paul police were sent to the home in the 600 block Cook Avenue about 4 a.m. after a neighbor called 911 to report Christopher Olson was “out of control” and assaulting his mother.

The charges said Olson opened the door and was hunched over his mother on the floor of the entryway, with his hands on her blood-covered face. She had extensive injuries to her head and face. A blood-soaked 2-by-4 board and a broken, bloody kitchen knife were found near her.

A woman, who identified herself as the “significant other” of one of Olson’s brothers, told police she heard Olson yelling at his mother, telling her that he was going to turn himself into jail. The woman said she saw Olson grab his mother by the face and push her. She said he looked at her “in a way that scared her,” the complaint said. She ran to the neighbor’s house for help.

Olson’s brother arrived on scene and told police that his brother was bipolar and had been “off his medications” for several months.

Olson declined to be interviewed by police.

Officers learned he had two outstanding warrants — one in Ramsey County for first-degree drug possession, the other for theft out of Dakota County.

Court records show Olson was convicted of domestic assault and related offenses a number of times in the past. His most recent previous felony case was filed in 2016 and he pleaded guilty to first-degree drug possession after a package shipped from Mexico to Christopher Olson at the Cook Avenue address was intercepted and found to contain methamphetamine, according to a criminal complaint.

Substance abuse or mental illness?

In January 2023, after mental health evaluations, Olson was found to have attained competency to stand trial. He waived his right to a jury trial in October, opting for a bench trial based on stipulated facts and evidence. He also changed his plea to not guilty by reason of mental illness.

On Dec. 15, Castro found Olson guilty of second-degree intentional murder, without premeditation, and also that he acted with particular cruelty.

The trial’s second phase — determining if the killing should be excused because of mental illness — was held over two days this month.

In Minnesota, an insanity plea, or “M’Naghten defense,” requires evidence that the defendant did not know right from wrong or understand the repercussions of his actions. The rule is named for a delusional man who tried to assassinate England’s prime minister in 1843.

The prosecution and defense introduced testimony and reports from two psychologists who diagnosed Olson with having severe bipolar disorder, with psychotic features, and stimulant use disorder.

The prosecution argued Olson should not be afforded the mental illness defense because his actions were the result of voluntary substance abuse.

Minnesota courts have consistently held that mental illness caused by voluntary substance intoxication is not a defense, Castro noted in his “findings and order,” filed Tuesday.

Olson has a long-documented history of methamphetamine use, Castro wrote. Medical reports indicate that, as early as 2010, Olson was using methamphetamine heavily. He tested positive for the drug in March and April 2021, and told an examiner he had been using it every other day in November. In a jail call, he told one of his brothers that he found something under the couch and smoked it before the killing.

“There is little doubt that (Olson) was using a substance of some form in the days or hours before the psychotic episode that caused him to murder his mother,” Castro wrote. “The question that can’t be answered with any degree of certainty, based on the evidence presented in this case, is whether the psychotic episode was induced by the voluntary intoxication or the mental illness.”

Judge’s conclusion

In reaching his conclusion, Castro said, he relied heavily on Olson’s history of mental illness and his continued manic and psychotic behaviors months after the killing. Olson did not have a rapid return to baseline after the killing, and has never been diagnosed with substance-induced mood or psychotic disorder, Castro noted.

The judge said he also relied on a psychologist’s diagnosis of Olson and her January 2023 report relating to his civil commitment. The report read, “Although he has used methamphetamine, his symptoms have persisted during periods of sobriety and within structured settings such as jail and while hospitalized.”

“Therefore, it is the conclusion of this Court,” Castro wrote, “that the defendant has proven by a preponderance of the evidence that when he committed this heinous act, he was laboring under such a defect of reason due to mental illness and did not know the wrongfulness of his acts.”

Castro ordered that Olson continue under his current civil commitment as mentally ill and dangerous.

Related Articles

Burnsville man fired more than 100 rifle rounds in incident that killed 2 officers, firefighter, BCA says

Western Minnesota man charged with fatally shooting brother during argument

Public memorial service for 3 fallen Burnsville first responders to be held Feb. 28

Blaine man pleads guilty to high-speed St. Anthony crash that injured 2

Winona coach accused of sexual misconduct with student-athletes