If they can't provide pretty substantial evidence that zimmerman initiated the physical confrontation, hell walk on self defense.
If zimmermans story that Martin confronted him holds up, that's all she wrote...
In many cases, they don't have anything but a dead guy, a gun, and a guy lawyering up. And in many of those cases, dude is found guilty without witnesses because he can't really prove why he killed the dude.
In this case... zimm killed a man. The events leading up to the shooting matter a great deal. If they didn't have that 911 call, MAYBE he could claim self defense with the bump and nose. however, the evidence really shows him being the aggressor... he's running after trayvon with a gun - as trayvon tries to escape - seconds before trayvon is killed.
but they still have to prove that Zimmerman wasn't getting the shit kicked out of him, at the time that he started to pull the gun, in addition to proving that Martin did not attack zimmerman first.
Is this true? The prosecutor cannot prove space aliens or ninjas didn't do it either.
I guess I find it hard to believe that I can go out once a week, shoot a man in the heart with no witnesses... come home with a few cuts... and as long as the system can't PROVE i wasn't attacked, I'm free to go?
I guess we'll learn a lot in this case... unless dude pleads to 8 to 11 years and serves 5.