That's an interesting half of the story; keyword being half.?ÿ Maybe the guy is simply loony, who knows.?ÿ I'd be curious to hear what the neighbor did if anything.
Shared gravel driveway. A boundary dispute I got involved in started with the neighbor running a business at the end of the shared gravel driveway with a lot of noisy early morning traffic. The boundary is just the culmination, the problem could be solved by basic good old fashioned neighborliness. Fortunately no one had a gun.
Guns are so great??PROBLEM SOLVED??one man dead, the other in prison for the rest of his life. Not like the movies.
I give his appeal about 0.1% chance of success. Every homicide defendant claims it was self defense. Dispatching the guy after he is down is not self defense.