Hmm, so they bad guy was outside and the homeowner came to the door with a loaded gun? Well, if the LE is happy with that explaination then I suppose I'll have to be as well. I feel for the guy's mailman, paper boy and the local girl scouts.
I have alarm sensors around the perimeter of my home that tell me if anything moves in my yard at night. It's wired for cameras, so I can click on any of them and see what's lurking out there via my TV. At 2:00 or 3:00 in the morning, if it ain't wearing a girl scout uniform, it's a no bag limit.
He may have known that someone was out prowling... either via electronics, like what I have, or the four legged variety of alarm.
I don't reckon the guy's mailman, paperboy or local girl scouts come sculking about in a ski mask just after midnight and fire into the house from outside, which is how this followup article reads:
http://accessnorthgeorgia.com/news/hall/newfullstory.asp?ID=110935
Looks like the homeowners are guilty of having a self defense weapon at hand within their home. I got a great idea, lets burn them at the stake.