Inset: Randall Grinwis (Ottawa County Sheriff’s Office). Background: The area in Michigan where Grinwis and his girlfriend lived before he killed her two years ago (Google Maps).
A 59-year-old man in Michigan will likely spend the rest of his life in prison for killing his girlfriend of 20 years, using his forearm to strangle her during an argument over the couple’s living arrangements and later telling authorities that he “snapped.”
Ottawa County Circuit Judge Karen Miedema on Monday ordered Randall Alan Grinwis to serve 32 1/2 to 90 years in a state correctional facility for the 2024 slaying of 63-year-old Donna Hyma, court records show.
Miedema handed down the sentence after a jury earlier this month found Grinwis guilty on one count of second-degree murder. Jurors also convicted Grinwis on one count of felony larceny for stealing $1,800 from the victim’s brother shortly after the murder.
During the hearing, Hyma’s family described the killing as a profound betrayal by someone they had trusted for decades.
“I trusted him with her life, and now I have to live with that for the rest of mine,” Hyma’s daughter, Lisa Vanderyacht, told the court.
Vanderyacht said she lost not only her mother, but also the man she believed Grinwis to be.
“I lost two people that day — my mother and the man I thought I knew for 20 years,” she said, adding, “We trusted him.”
She also rejected any suggestion that the killing was a momentary lapse, borrowing the defendant’s own words to make her point.
“Nothing about that day was different,” she said. “He just snapped.”
But according to prosecutors, saying Grinwis “snapped” actually underplayed his level of culpability in Hyma’s death. The state continued to assert that the violence he inflicted on his girlfriend was far from instantaneous, emphasizing the sustained nature of the attack.
“This was not a snap,” a prosecutor said. “He had 40 seconds to change his mind, but he continued pressing down on her, and that cannot be overlooked.”
Miedema, in imposing the lengthy sentence, called the case “a very sad situation,” stressing that the killing was preventable.
“This was an incident that could have been totally avoidable,” the judge said. “You had options … but you chose a very drastic and very evil option.”
Grinwis declined to make a statement before sentencing.
As Law&Crime previously reported, the killing happened on New Year’s Day 2024 inside the couple’s Zeeland Township home following an argument over living arrangements.
Hyma was found unresponsive on a couch after deputies conducted a wellness check. An autopsy later determined she died from asphyxiation, and her death was ruled a homicide.
Prosecutors said Grinwis used his forearm to press against Hyma’s throat, suffocating her. He later checked for a pulse and breathing to confirm she was dead, according to court documents.
After the killing, Grinwis stole money from the victim’s brother and fled the state. He traveled through the Midwest before flying to Las Vegas, where he stayed in a hotel and gambled until he ran out of money.
Investigators said Grinwis eventually turned himself in to police, though prosecutors alleged he did so only after exhausting his funds and told authorities he would have “kept running” if he had the means.
A recording of the confession was played during trial, with jurors hearing Grinwis telling detectives how he just “snapped,” according to a report from The Sentinel.
“She was saying some really crazy s— and I’m telling on myself right now and I snapped,” he said on the tape. “I don’t know how else to say it.”
He went on to say that he could not remember exactly what made him lose his temper.
“I don’t know what made me snap,” Grinwis reportedly said. “I honestly don’t. That’s what hurts the most for me.”
