It would be different if it was self-defense. If I understood the story correctly, the surviving man followed the victim to a neighborhood, and that is where they got in a fight. I can blame him for that. He obviously doesn't deserve murder-level prison time, but the fight wasn't an accident. He needs serious consequences.

I think I would feel differently if the surviving man was the one followed. In that case, I may be trying to "let it go" but if he follows me to my own home, it is self-defense--even if I was the one who did the brake-check.