Man Charged in Bigfork Double Homicide Pleads Not Guilty

A 37-year-old man accused of killing two Bigfork residents in their home last October pleaded not guilty Thursday to two charges of deliberate homicide, a third felony charge of tampering with or fabricating evidence and a fourth felony charge of criminal possession of dangerous drugs.

Derrick James Jackson entered the pleas during a Feb. 16 arraignment hearing in Flathead County District Court before Judge Amy Eddy.

According to an affidavit filed Feb. 7 by Deputy Flathead County Attorney Amy Kenison, a Flathead County Sheriff’s Office (FCSO) investigation connected Jackson to the alleged murders of Stanley Grotberg, 65, and Tricia DeMotts, 62, whose autopsies revealed gunshot wounds to the head last Oct. 28.

Last year, FCSO deputies responded to Esteban Lane in Bigfork on Oct. 28 to a report of a male wearing a leather jacket and a fedora who was holding a pistol and power tool and attempting to break into cars and houses, according to charging documents.

Deputy Aaron Westphal arrived to find Jackson, who was reportedly outside of a residential property holding the power drill. When he was commanded to drop the drill and come forward, he turned the opposite direction and said he was going to be sick. He eventually followed orders and approached Westphal. When he was asked what he was doing, Jackson said he was looking for his relatives but couldn’t give an explanation why he was at the property.

Authorities searched Jackson for weapons and found a loaded magazine for a Smith and Wesson .40-caliber semi-automatic pistol and a bottle of medication prescribed to Grotberg. Authorities observed dried blood and small abrasions on Jackson’s hands and drops on his pants, which he said was there because he was punching trees.

A search of the area where Jackson was seen earlier revealed a cordless drill and a loaded Smith and Wesson .40-caliber semi-automatic pistol that matched the magazine found on Jackson.

When asked about the pistol, Jackson said he took the pistol “from somewhere but could not remember where.” Methamphetamine was also found on Jackson during the search.

Jackson was arrested and booked in the Flathead County Detention Center on a parole hold, where he remains.

Following Jackson’s arrest, Westphal returned to Esteban Lane in Bigfork to try to contact Stanley Grotberg, who did not answer the door but had his vehicle parked near the house with the interior lights and television on. Westphal looked through the glass in the door and noticed blood on the floor, refrigerator, and on a mop.

Authorities entered the home for a welfare check where they found Grotberg and DeMotts deceased in a bedroom along with blood and .40-caliber casings.

Jackson later confirmed he was living with Grotberg and DeMotts, but he declined to speak further with officers. He later spoke with individuals who visited him in jail, telling them he was defending himself and that nobody else was present.

According to court records, Jackson has a lengthy criminal history, which includes a conviction for criminal possession of dangerous drugs in 2019, and multiple theft and burglary charges dating back to 2004. Jackson remains in the Flathead County Detention Center, where he has been since Oct. 28, on a $1.5 million bond. He’s scheduled to stand trial on April 10.