A Portland woman who at first claimed she accidentally shot her husband in the head last year while reaching for a bag of potato chips admitted to pulling the trigger during an early-morning argument.

Mariah Decker pleaded guilty Monday to criminally negligent homicide for firing a single shot at her partner of 20 years, 44-year-old William Decker, as they quarreled about 2 a.m. April 22, 2023, inside Unit 438 of the Las Adelitas apartments on Northeast Killingsworth Street in the Cully neighborhood.

Multnomah County Circuit Judge Christopher Ramras sentenced Mariah Decker, also known as Mariah Cole, to six years and three months in state prison as part of a deal with prosecutors.

The now 41-year-old called 911 after the shooting but initially claimed she was searching the snack cabinet when a handgun tumbled out and “just went off,” according to a search warrant filed earlier.

“I killed my baby,” she said, according to the warrant. “I didn’t mean to do this.”

Decker didn’t address the judge during sentencing, but previously filed a letter to the court saying William Decker had kept her living under a reign of terror. They had moved to Oregon from Ohio just a year before the killing.

“I went from being chased across the country by a narcissistic abuser who kept me homeless,” she wrote, “to being in a jail cell.”

Investigators found Mariah Decker’s initial explanation dubious, prompting her to acknowledge during a police interview that she had pulled the trigger, the warrant says.

The plea deal ended the case before Mariah Decker was ever formally indicted. She had been held in jail on suspicion of second-degree murder.

There was no camera footage or independent witnesses to the shooting.

As the plea hearing concluded, defense attorney Alexis Andersen said her client still has much to offer.

“I really hope she can learn some skills in DOC to move forward and put some of the trauma she’s experienced behind her,” Andersen said, using an acronym for the state Department of Corrections. “She has a lot of life left to live.”

—Zane Sparling covers breaking news and courts for The Oregonian/OregonLive. Reach him at 503-319-7083, zsparling@oregonian.com or @pdxzane.

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