This guy pulled a gun and followed another man who had his own gun. The other guy was walking away, as if he was trying to avoid the situation. The guy following him has his gun drawn and won't stop following him, and it looks like he tries to fight the guy - maybe even put his gun down. Then it sounds like the second guy lets off a warning shot. Then the aggressor goes to pick up his gun and the second guy pops him in the head. End of story. Is this murder or self defense?