A Flathead County judge on Tuesday, June 17, 2025, sentenced Derrick Jackson to 100 years in the Montana State Prison for the 2022 shooting death of Stanley Grotberg in Bigfork.
Judge Amy Eddy handed down the sentence, which includes 80 years for deliberate homicide with no time suspended.
WATCH THE SENTENCING:
Jackson was found guilty in April of killing Grotberg but was acquitted in the death of his mother, Tricia Demotts.
Both Grotberg and Demotts were found dead in their Bigfork home following a violent dispute in October 2022.
Eric Grotberg, Stanley Grotberg's son, delivered an emotional victim impact statement before the sentencing.
"I believe because of the impact it had on our lives and it will be for the rest of our lives. He should receive the maximum sentence," Eric Grotberg said.
John Jackson, Derrick's father, testified as a character witness for his son.
"I believe 100% he did not shoot his mom, he loved his mom. There's no doubt I believe he took the gun from Stan after he shot his mom and shot Stan when he was coming after him," John Jackson said.
In addition to the homicide charge, Jackson received 10 years for tampering with evidence and another 10 years for use of a firearm.
(FEBRUARY 8, 2023) Prosecutors have charged Derrick James Jackson with the murders of 65-year-old Stanley Allen Grotberg and 62-year-old Tricia Lynn Demotts at their home in Bigfork.
Jackson has been charged with two counts of deliberate homicide, one count each of tampering with or fabricating physical evidence, and criminal possession of dangerous drugs.
According to charging documents, Flathead County Sheriff's deputies took Jackson into custody on October 28 after receiving reports of an armed man breaking into homes on Esteban Lane in Bigfork.
Deputies found Jackson holding a power drill on the Estaban Lane property. He told deputies he was looking for relatives in the area but couldn't say why he was in that specific area.
A search turned up a loaded magazine for a Smith and Wesson .40 caliber pistol and a prescription bottle with Grotberg's name on it.
Deputies said in charging documents they returned to Esteban Lane to track down Grotberg.
They found Grotberg's vehicle in the driveway and saw lights on in the home, but no one answered the door.
Deputies then discovered the bodies of Grotberg and Demotts in a bedroom, surrounded by blood and .40 caliber casings.
An autopsy determined both people died after being shot in the head.
Throughout the investigation, Jackson told detectives he lived with Grotberg and Demotts but declined to speak further with authorities.
Jackson is currently being held in the Flathead County Detention Center on $1.5 million bail.
He is expected to make his initial appearance Wednesday.
