Attorney Susanne Gustin says Eric Charlton plans to plea Oct. 23 to misdemeanor negligent homicide and carrying a dangerous weapon under the influence.
He'd previously been charged with felony manslaughter, but the count was dismissed last month.
Eric Charlton's 17-year-old brother, Cameron, was shot in the head May 28 while camping with family and friends at Yuba Lake State Park in Juab County.
Court documents say the two brothers and a friend were drinking around a campfire at about 3 a.m. when Eric Charlton began demonstrating firearm techniques and his .45-caliber handgun went off.
Gustin calls the shooting "absolutely an accident."
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