I’ve always believed it was Zimmerman’s weak fat azz on the ground screaming. Zimmerman's actions led to a fight with a barely 17 y/o kid and lost, then Zimmerman pulled and fired his gun out of fear. Trayvon was standing his ground in accordance with Florida law, which includes using force to protect yourself.
Zimmerman killed Trayvon on a sidewalk, not at a street corner looking up at a street sign. The one eyewitness who says Trayvon was beating Zimmerman didn’t say he saw Trayvon start the fight. He just saw Zimmerman losing the fight and screaming for help.
I believe Zimmerman is guilty of making this kid fear for his safety by following him, even after Trayvon tried to run from the guy. So, Trayvon tried to stand his ground against a perceived threat and was killed by a fat coward. Trayvon could have thought that Zimmerman was a pedophile, child abductor, etc.
I also think Zimmerman was a little high that night because his voice sounds different on the 911 tape vs the voicemail message he left for a friend the other day. You’ll notice Zimmerman’s speech was slow, slurred, and lethargic on the 911 tapes and fast and strong on the voicemail. The police should have checked Zimmerman for drugs and alcoholic use.