Walk Through Someone's Backyard, and it Proves You're a Criminal; Defend Yourself by Throwing a Punch, and He has the Right to Kill You

   Here are the facts of the case. Do they justify murder? We have a kid who went to the store, and took a shortcut home, cutting through backyards, who is followed by a neighborhood watch person, who police told to back off, who decided not to back off, who confronted a probably scared boy, and a fight ensued, and the scared boy probably ended up on top and punched the pursuer, and the man pulled a gun and killed the boy. How far off is it that those are the facts?
   Just look at these facts, and say whether they justify murder?