A Cheyenne man accused of fatally shooting his roommate in Nov. has pleaded not guilty to voluntary manslaughter.

Cody Hess was arraigned this (Tuesday) afternoon in Laramie County District Court.

Charging documents allege Hess killed 35-year-old Michael Robbins by shooting him twice in the chest with a 9mm handgun. Hess' attorney, Devon Petersen, says Hess acted in self-defense after Robbins attacked him.

Assistant Laramie County District Attorney Benjamin Sherman asked that Hess' bond be increased to $10,000 cash, arguing that Hess has "assaulted others by pointing firearms at them," but Judge Steven Sharpe denied the request.

Hess' trial -- which the state estimates will take a week -- has been tentatively set for March 6.  If convicted, Hess could face up to 20 years in prison.