a citizen used the officer's radio to call for help. bolton was found at the scene. he died later at the hospital. the memphis mayor spoke about the challenges faced by his officers. >> this again evidence the fact that there are so many guns on our streets in the wrong hands. that's the key thing. and the men and women in blue have certain rules of engagement that they have to follow. but at any given minute in a 24-hour day, they're dealing with folks who have no rules of engagement. >> it is unclear what could have led to the shooting. let's talk about it with tom fuentes, former fbi assistant director also formerly a police officer himself. the first thing that comes to mind, a citizen saw what had happened in the aftermath, used the officer's radio in his car