Looked to me like the guy who got shot had partial custody of his kid, showed up at the appointed time to pick him up, and his wife would not produce the kid.
If that's true, I don't blame the "trespasser" for getting pissed and not leaving. And I wonder how that would change the culpability of the wife. If she was denying him his visitation, she had to know that would set him off.
If all that's true, and it may well be, then his solution was to report it to the courts and arrange to have Sheriff's Deputies with him every time he comes to pick up his kid till his wife starts cooperating with the court orders. Getting in the face of a guy who comes out of his home with a gun and demands you leave isn't the right move.
