PA test of Castle Doctrine and/or No Retreat
Hard to tell which from this story. It might really have been a test of neither. Two drunken aggressors come into a person yard with baseball bats, pursue him, continue to menace him even after he displays a gun, and he takes a hit in the head before firing. You don't need castle doctrine on those facts. *If* PA were a "retreat" State before, maybe stand your ground helps some, but even with a retreat requirement, turning his back on the aggressors increased his danger (and a 42 yr old isn't likely to outrun two guys aged 19 and 34, either).