A Florida cop who accidentally shot and killed an innocent woman during a police exercise was sentenced to 10 years of probation. On Aug. 9, 2016, retired librarian Mary Knowlton attended a police simulation explaining the use of lethal force, together with 30 other civilians. Knowlton role-played a cop in a demonstration while Officer Lee Coel pretended to be a bad guy with a gun. Coel said he didn't know the gun was loaded with live ammunition. She was killed.