“Which known facts, the ones where zimmerman (armed with a loaded sidearm) got out of his car to follow and martin (unarmed) ran away, are those the facts you mean?”
Your description seems to paint a picture that Martin only ran when Zimmerman exited his car, gun exposed, which prompted Martin to take off running in fear. If that was your intent the I say bull hockey.
Zimmerman was on his phone with the police, in fact in mid sentence, when Martin suddenly turned and ran off. In the 911 recording you will see that it is crystal clear that only after Martin takes off does Zimmerman exit his vehicle and head in the direction where Martin disappeared.