So the initial report of this suggested that it happend February 2013, but instead was 2006. I had all of this typed out as if it was a current (and overlooked) case, but there are still some things that people can take away from this altercation.
Local News
http://www.AFB.com/story/4527526/Additional info containing protests to a "traffic stop killing"
http://floppingaces.net/2006/02/22//Summary of the situation: A cop is writing a guy a ticket.
Bad guy freaks out on the cop and tackles him so that the cop is pinned on his back with the bad guy beating the crap out of him.
The cop yells for help and manages to shoot the bad guy in the abdomen with one round. Fight continues.
CHP holder (who walked with a cane and had a neck brace), after hearing screams and seeing the cop getting bashed, scuttles over to his truck to retrieve his 45 ACP, returns and orders the bad guy to stop.
Bad guy doesn't stop. CHP holder shoots 4 shots into the bad guys chest and abdomen.
Bad guy doesn't stop and continues to bash the cop. CHP holder then shoots the bad guy in the head ending the situation.
Without any more reports than this one article there is still some information that would be valuable. It is a good thing that the CHP holder was able to come to the aid of the police officer, but it took 6 shots (5 to the body at close range, and 1 to the head) for this bad guy to stop his attack.