MITCHELL — A Mitchell man involved in a serious motorcycle crash last summer has been charged with driving under the influence and pleaded not guilty Tuesday morning in Davison County felony court. Tyler Bier, 35, also denied an alleged violation of probation tied to a previous Class 5 felony conviction for possession of cocaine. Bier previously served as a deputy with the Davison County Sheriff’s Office. Attempts to reach Bier’s attorney, Richa…