I think at this point, I'd have to say that just by listening we don't know who was screaming for certainty, Zim says it was him, while handcuffed in the back of the squad car, and Treyvon's mother says that that was Trey's screams. Injuries to the back of the head, and nose on Zim are inconclusive alone as to who attacked whom, as are the grass stains. Treyvon was reported by Sanford police as also a resident of the neighborhood, so obviously there is nothing suspicious about him being on the sidewalk at 7:30pm at night for God's sake. Zim seems to have a history of 911 abuse IMHO, reporting everything from an open garage door, which is ok, to a pothole in the road, which isn't. Treyvon being a handful in school, and currently being suspended are not the issue here, and have no bearing, all I would say on that is that he's 17 years old...Anyone with children all either know, or have a child which rebel's a little at that age, doesn't warrant a death sentence.
Over all, I think I'd still have to say that this is a tragic case of Zimmerman taking a course that was fueled by adrenaline, over confidence due to carrying a gun, maybe misinterpretation of what his duties of NW were, and what the meaning of meet force with EQUAL force means.
Zimmerman pursued this young man, hunted him down, got into a fight, and was losing that fight and used his gun to gain advantage killing Treyvon. That is what we know. And based on that, Zimmerman is in the wrong here. Now it isn't in my mind murder, but it is negligent homicide.
j-mac