A 19-year-old Oklahoma woman could spend the rest of her life in prison after she and her boyfriend murdered her grandparents “because she wanted them dead.”

Heidi Dutton, who was 17 at the time of the murders, was sentenced to life in prison on Friday for the slayings of Larry Dutton, 73, and Deborah Dutton, 67. The defendant pleaded guilty to two counts of first-degree murder and desecration of a corpse, plus conspiracy to commit murder. She must serve 85% of a 45-year sentence — which is a shade over 38 years — before becoming eligible for parole.

Her boyfriend, 22-year-old Lucas Anthony Walker, was sentenced to 35 years in federal prison as he is a citizen of the Cherokee Nation.

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“This was a calculated and brutal crime, but the law requires us to weigh youth and culpability,” Washington County District Attorney Will Drake said in a statement. “This sentence holds Heidi Dutton accountable, mirrors the sentence imposed on her co-defendant, and spares the victims’ family the trauma of trial and years of appeals.”

Authorities say Dutton and Walker killed her grandparents a few days before Christmas Day 2022. Neighbors and family members became concerned about the victims after not hearing from them and called cops to complete a welfare check at their home in Dewey, some 50 miles north of Tulsa. According to the federal complaint, deputies from the Washington County Sheriff’s Office conducted a search of the home on Jan. 20, 2023, and discovered the elder Duttons buried in a shallow grave in the backyard.

“[Dutton] was determined to be the adopted daughter, and biological granddaughter, of the two victims,” the complaint notes.

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Blood had been cleaned from the victims’ bedroom but some seeped into the floorboards. Both suspects admitted to killing the victims in interviews with cops. Heidi Dutton said it was her boyfriend who murdered her grandparents at her behest.

Walker told investigators he entered the Dutton home on Dec. 19, 2022, as the victims slept. He took a .22 caliber pistol from the home and waited in his girlfriend’s bedroom until he heard noises coming from the victims’ room. He waited outside the bedroom until Deborah Dutton opened the door. Walker then shot her in the face, authorities said.