A Prunedale man has pleaded not guilty to murder and elderly abuse after allegedly killing his father. Police officers found the body of 70-year-old Jerry Roberts while performing a welfare check at his residence last month. The victim’s son, 34-year-old Matthew Roberts, was arrested in connection with his death. Roberts has a prior conviction for shooting his stepfather in 2005 and has been diagnosed with paranoid schizophrenia. He is due back in court April 16th for a preliminary hearing.