Trial to determine if mental illness played role in slaying of mom, son in Otter Tail County

William Hillman

FERGUS FALLS, Minn. — A Pine River, Minn., man found guilty of bludgeoning a woman and her son to death more than two years ago in Otter Tail County is headed to the second phase of his trial, which will decide if his mental health can be used as a defense.

Otter Tail County Judge Kevin Miller found William Lynn Hillman, 24, guilty on two second-degree counts of murder in June for the deaths of 42-year-old Denise McFadzen and her son, 21-year-old Dalton, according to court documents.

A scheduling hearing is set for Oct. 2 to determine when the second phase of the trial will begin. Unless Hillman wants Miller to make the decision, that's when a jury will determine if mental illness prevented him from understanding that killing the McFadzens was wrong at the time of the offenses, County Attorney Michelle Eldien said.

If the jury or judge finds he is not guilty by reason of mental illness, Hillman will be committed to a treatment facility. If mental health did not play a role in the crime, he will be sentenced.


Denise Mcfadzen and Dalton Mcfadzen
Denise Mcfadzen and Dalton Mcfadzen

Each count is punishable by up to 40 years in prison.

The findings of guilt by Miller stem from a review of evidence linked to the 2018 killing in the McFadzens's mobile home in Frazee, Minn. Hillman lived with the mother and son, who died of blunt-force trauma to their heads, according to autopsy reports.

Hillman claimed he “blacked out” but knew he did a “bad thing” when he came to his senses, investigators said. Prosecutors alleged he bludgeoned the McFadzens to death with a pipe wrench.

In May, attorneys agreed to have a trial without witnesses or a jury, meaning Miller was allowed to make a ruling based on evidence alone. Hillman has maintained he is not guilty by “reason of mental illness or deficiency.”

Hillman has a history of schizophrenia, according to court documents from a 2016 case in Minnesota. A Cass County, Minn., judge ruled he was unfit for trial when he was accused of attacking and threatening to kill his mother in April 2016 at her Pine River home.

A doctor found Hillman, who was 19 years old at the time, had a "very substantial thought disorder" that grossly impaired his judgment and capacity to recognize reality, court documents said. The doctor also said he posed a threat of physical harm to others.

Hillman pleaded guilty in May 2017 to a felony charge of making threats of violence, and other charges were dismissed. However, the court found him not guilty by reason of mental illness.


He was taken in June 2016 to St. Peter Regional Treatment Center, according to court documents. Then he was released in November 2017, about five months before the McFazdens died.

A doctor found in June 2018 Hillman was not yet fit to face prosecution. The doctor reversed that finding in January 2019, saying Hillman's competency had returned and criminal proceedings could continue.

The court has not received a report from the doctor regarding conclusions about whether Hillman was culpable at the time of the killings.

A second doctor said the defendant met the standard to use mental illness as a defense. Miller signed another order on July 20 for the defendant to participate in a mental health evaluation at the request of Hillman's attorneys.

It’s unclear when the evaluation will be completed. Once turned into the court, prosecutors and the defense will have 10 days to review the findings and object, if they choose to do so.

April Baumgarten joined The Forum in February 2019 as an investigative reporter. She grew up on a ranch 10 miles southeast of Belfield, N.D., where her family raises Hereford cattle. She double majored in communications and history/political science at the University of Jamestown, N.D.
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