When Zimmerman stopped his car, Martin was walking away. He got out, against the advice of the 911 operator and Neighborhood Watch protocol, because he thought he would lose sight of Martin. His testimony. Every second that passed, Martin was one step farther away. If Zimmerman walked in the same direction, but more slowly, Martin would probably not have seen him, and the distance between them would have grown. If he had walked at the same speed as Martin, the distance between would have remained the same, and there would have been little chance of an altercation.
Thus it is demonstrated: Zimmerman closed the distance, he walked faster, he pursued, he initiated.
And Martin became aware of someone closing on him, alone in the rainy dark. Who? Not a cop. Why?
How did Martin respond? He could have have run away. He could have stopped, turned, and waited, or even moved towards Zimmerman. What did Zimmerman say? What did Martin say? Who touched or pushed or punched first? Who was more afraid? Why wasn’t a brief conversation enough to resolve things?
All unknowable, unless you are Zimmerman. My guess is Martin declined to accept the authority Zimmerman asserted. Lacking command presence, a badge, a uniform, or any actual authority, Zimmerman pulled what he had, his gun. In terror, Martin lunged, Zimmerman fired. Or Martin punched him first, not liking the guy who chased him down, fearing a mugging.
Point is Zimmerman didn’t get the submission he was seeking, so he killed the kid. And there isn’t a narrative to excuse that.
Quod Erat Demonstratum
Tighter still: didn’t like the look of that boy, so he killed him. He was frightened, of course he was. Repeat.