More charges have been filed in the investigation into the shooting death of a State Highway Patrol officer. Lance Shockley is already charged with ambushing Patrol Sergeant Carl Graham last month outside Graham’s home in Van Buren and shooting him to death. Shockley’s wife, Coree Shockley, had been accused of tampering with evidence in the case. Now, a felony charge of assaulting a law enforcement officer has been added. And, Coree Shockley’s sister and mother have been charged with interfering in the investigation.