PRINEVILLE, Ore. -

A Prineville man pleaded not guilty Wednesday to second-degree manslaughter and other charges in a fatal ATV crash earlier this year, Crook County District Attorney Daina Vitolins said.

Mason Edward Stafford, 31, was arraigned on the indictment that also charges him with criminally negligent homicide and two counts of recklessly endangering.

Tyler Robert Pierce, 22, died at the scene of the crash the night of Saturday, Feb. 1 as he, Stafford and a third person rode an ATV on private property off NE Barnes Butte Road, north of Prineville, sheriff’s deputies said. The Polaris Ranger 900 overturned and came to rest on its top.

Undersheriff John Gautney said alcohol was believed to be a contributing factor in the crash.

A pre-trial conference in the case is scheduled for May 28th, Vitolins said.