Apparently the trooper was responding to a roll over accident when the suspect shot the trooper and then assaulted him. The Good Samaritan asked the trooper if he needed help, which he replied yes, the citizen got his gun and told the suspect to stop banging the troopers head against the ground and when he wouldn't, shot him and killed him. Good for him.
From that article:
http://www.breitbart.com/2nd-amendm...suspect-beating-az-state-trooper-on-roadside/
From that article:
Also on January 12, the New York Times editorial board wrote against expanding the opportunities for armed citizens to be armed for self-defense. The paper claimed, “The grim truth is that concealed-carry permit holders are rarely involved in stopping crime.”
http://www.breitbart.com/2nd-amendm...suspect-beating-az-state-trooper-on-roadside/