The answer is d: Urban legend

It's not really an urban legend (although it became one), it's just a hypothetical thought problem.

The story opened the movie Magnolia with two other UL-ish tales, in that case illustrating the theme of happenstance.

Wikipedia (not really better than the Snopes article, though).

OK, now it is better! (Breaks arm patting self on back)

It was also used as a story line on C.S.I. and Homicide: Life on the street.

I think the father would be charged with involuntary manslaughter. Suicide it isn't, because the jumper would have survived the fall, and had no intention of killing himself at the time he loaded the gun. If he had survived the shooting, he would have been charged with attempted murder, and the father with, maybe, reckless endangerment or something. I don't think "accident" applies because if no one had done anything illegal, nobody would be dead. And we have four instances of illegal activity here: loading the gun with intent to murder, threatening someone with a gun (even if it had been unloaded), endangerment (not checking if the gun was loaded), and attempted suicide. If any one of these things had not occurred nobody would be dead; so, no accident.

In any case, if you peel away all the wacky coincidences you are left with a shooting death - the same as if the son hadn't been falling by the window, and the father had instead hit the neighbor in the apartment across the street.

/talking out of my non-lawyer ass

So, to me it seems like a fun story, but not really that difficult to tease out.

See? See that right there ^? That's why I heart taz. Well, that and her mad phoneskillz.