In my mind premeditiation implies planning of a crime before its commission. Running to get a gun to use against an assailant/tresspasser doesn’t seem like planning prior to commission.
In the legal sense, my friend, not in the common, everyday sense. Dear ol' dad armed himself with a deadly weapon (to wit, a pool cue) before he even entered the bedroom and discovered the kid hiding in the closet. Then, after beating him with the pool cue, he left the scene (thereby obliterating his heat of passion defense) to get a more deadly weapon (to wit, a gun), return to the scene, and use that more deadly weapon to continue what he had begun.
He's in deep sh*t. His ways out are two: plea bargain, or pray to God his defense attorney has the best voir dire of his entire career. Or of any criminal defense lawyer's career since the OJ Simpson trial.
Running to get a gun to use against an assailant/tresspasser doesn’t seem like planning prior to commission.
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OK. How about the situation as it actually happened? Running to get a gun to use against the boy you know your daughter invited into the house when you were gone, when you knew before you got there that the boy was in your house by your daughter’s own invitation does or does not sound like premeditation.
Try to remember that he was alerted to the situation ahead of time. From the linked story: “He said a friend called that morning to say Guzman’s car was parked down the road.”
He wasn't assaulting anyone and wasn't trespassing if the daughter invited him in. The father could 'uninvite him' but in any case, isn't justified in shooting him.