More updates to come. By Rob Alway. Editor-in-Chief. LUDINGTON — Eric John Knysz, the 20-year-old Irons resident who murdered Michigan State Police Trooper Paul Butterfield, will spend the rest of his life in prison. He was sentenced today in 51st Circuit Court to life in prison without parole. For the first time, since Knysz murdered Trooper Butterfield on North Custer…