Alright, here it comes. We now know that Trayvon Martin had traces of Marijuana in his blood at the time of death. This seems to vindicate a statement made by Zimmerman during the phone call with the police where he describes TM as "looking high" (He looks high". In this moment, GZ made a profiling on TM and acted accordingly. It turns out that this was a justified profiling: Zimmerman knew what to look for.
Like I sadi before, we know that there is a very high correlation between drug use and crime. Therefore, GZ was probably not unjustified in calling the police form his car. However, TM noticed GZ and took off during the call. We can hear GZ getting out of his car and following until the police tell him to stop. At that moment, we hear GZ catch his breath and pant a little.
I can go more into where he probably was at that moment in another post, but I want to mention the injuries reported by the prosecution. First, we know that in addition to the gashes on the back of his head, GZ had a broken nose and two black eyes. He has no wounds on his hands though. As for TM, we know he had a gunshot wound fired from point blank range. He also had some wound on his hands, on the outside of his ring finger.
This evidence supports an analysis that Trayvon did punch Zimmerman and that Zimmerman did not fight back until actually shooting TM. This does not sound like a murder. Or even a manslaughter. This sounds like normal self defense. I hope GZ walks free and gets his life back.