In regards to the discussion on duty to retreat, I believe the time for retreat was BEFORE the pipe was swung. Once hit in the head, the victim is under attack and defense becomes necessary. At that point, I'd think duty to retreat isn't a factor any more.
Originally Posted by cheapo
A car ding is no reason to hit a guy over the head, and not a good reason to die for.
Nope, a dinged car shouldn't have come to this, but the guy that died didn't die because of the ding. He died becase he attacked another individual with a deadly weapon (the pipe). There was an exit point in the altercation that the pipe-swinger could have taken to end the incident, but he chose attack instead, which is (as well it should be) treated as a whole new incident.