http://www.freerepublic.com/focus/news/3878784/posts?page=30#30
See my post 23 with my amateur description of the live stream video from that night. Although I’m now positive that who I thought was the pistol gunman by the light is actually reporter McGinnis. The pistol gun man that shot first is offscreen to the right, behind McGinnis.
McGinnis is the guy that took off his shirt. He stated there was a gunshot from behind him (and thus behind Rosenbaum) and that was when Kyle turned, Rosenbaum caught up to Kyle to reach for the rifle and Kyle defended himself.
Post 26 has more conjecturing on my part!
I saw McGinnis on Tucker. Tucker almost asked another question at the end of the interview, then bit his lip. McGinnis knows or did more than he let on.