A Poplar resident, Michael J. Ackerman, 74, pleaded guilty to charges of second-degree murder and use of a firearm during a crime of violence in federal court, according to U.S. Attorney Kurt Alme.
Ackerman faces up to life in prison, a $250,000 fine, and five years of supervised release. The sentencing will be determined by Chief U.S. District Judge Brian M. Morris on June 3, 2026. Ackerman remains detained until further proceedings.
According to court documents presented by the government, law enforcement responded to an incident in Billings on September 14, 2025. Officers were informed that Ackerman had admitted to killing three individuals identified as Jane Doe 1, John Doe, and Jane Doe 2. Deputies made contact with Ackerman at his residence.
After being read his Miranda rights and agreeing to speak with officers, Ackerman described events from September 11, 2025. He stated that he and others in the house were using methamphetamine when he became suspicious they were “setting him up.” While in the bedroom with Jane Doe 1—who was holding a pistol—Ackerman picked up his own Smith and Wesson 9 mm pistol and shot her twice in the head. He then went into another room where John Doe and Jane Doe 2 were sleeping and shot both individuals.
Ackerman told law enforcement that they would find the deceased at his house in Poplar.
Fort Peck Law and Justice Department officers obtained a telephonic search warrant from Fort Peck Tribal Court after receiving no response at Ackerman’s home early that morning. Upon entry around 5:30 am, officers found the bodies of Jane Doe 1, John Doe, and Jane Doe 2 inside; all had gunshot wounds and four spent nine-millimeter casings nearby.
The case is being prosecuted by Assistant U.S. Attorney Kalah Paisley. The investigation involved the FBI, Fort Peck Tribes Department of Law and Justice, and Yellowstone County Sheriff’s Office.
