Prosecutors charged a 37-year-old man Tuesday with the murders of two Bigfork residents last fall.

Derrick James Jackson faces two counts of deliberate homicide in Flathead County District Court and one count each of tampering with or fabricating physical evidence and criminal possession of dangerous drugs. He is being held in the county jail with bail set at $1.5 million. His arraignment before Judge Amy Eddy is scheduled for Feb. 16.

The Flathead County Sheriff’s Office, which investigated the case, quickly deemed the deaths of 65-year-old Stanley Allen Grotberg and 62-year-old Tricia Lynn Demotts as likely homicides. Authorities said at the time that they found the couple while deputies conducted a welfare check on Oct. 28.

An affidavit filed in district court Feb. 7 indicated that the discovery of the bodies came after deputies took Jackson into custody while responding to multiple reports of an armed man breaking into homes and houses on Esteban Lane in Bigfork.

Deputies allegedly found Jackson on an Estaban Lane property holding a power drill in one hand. Ordered to drop the power tool and come toward the deputies, Jackson said he felt sick and walked the other way, according to court documents.

Eventually cooperating with authorities, he told the deputies he was looking for relatives in the area, “but couldn’t give an explanation of why he was at this property,” court documents said.

A subsequent search allegedly yielded a loaded magazine for a Smith and Wesson .40 caliber pistol and a prescription bottle with Grotberg’s name on it. A jewel bag also found on Jackson contained a crystalline substance, which was later sent to the state crime lab, where it tested positive for methamphetamine, court documents said.

Deputies also reported noticing dried blood on Jackson’s hands and droplets on his pants. According to court documents, Jackson said he punched a few trees earlier in the evening, though he sported only small abrasions on his hands.

Checking the area where Jackson left the drill, deputies found a loaded Smith and Wesson .40 caliber pistol dropped in high grass, court documents said. Asked about the semi-automatic, Jackson allegedly said he took it, but could not remember where he found the weapon.

While authorities took Jackson to the county jail, deputies attempted to track down Grotberg, who lived on Estaban Lane, court documents said. They found a vehicle parked in the driveway and saw lights on inside as well as a television, though no one answered the door.

Peering through a window, deputies spotted a drop of dried blood on the floor and a bloody mop, court documents said. Checking the home, they found the bodies of Grotberg and Demotts in a bedroom, surrounded by blood and .40 caliber casings, according to court documents.

Both died after being shot in the head, an autopsy later determined.

During an interview with detectives, Jackson allegedly said he lived with Grotberg and Demotts before declining to speak any further with authorities. But while receiving a visitor at the county jail, Jackson allegedly said he had defended himself, according to court documents.

If convicted, Jackson faces between 10 and 100 years in state prison for deliberate homicide. As both allegedly involved a firearm, prosecutors can seek an additional two to 10 years behind bars.

Tampering with or fabricating physical evidence carries a maximum penalty of 10 years in prison and a $50,000 fine. Criminal possession of dangerous drugs is punishable by up to five years behind bars and a $5,000 fine.

News Editor Derrick Perkins can be reached at 758-4430 or dperkins@dailyinterlake.com.