Sorry, but no...

this was most certainly not an accident:

When Justin Cardenas emerged from a 14th-floor room at the Emily Morgan Hotel two years ago with blood smeared on his shirt and hands, he immediately acknowledged committing a horrible accident while playing with his best friend's gun, authorities said.
...
The two had just checked in at the downtown hotel for a get-together with friends later that night, Cardenas, 23, told authorities. The friends were alone in the room when Halsell took out the clip of his .45-caliber handgun and put the firearm to his head, taunting Cardenas to pull the trigger, the defendant said.

Thinking it was a joke and the gun was unloaded, Cardenas said he pulled the trigger. It fired.

What's Rule No. 3 again? Never point the gun at anything you don't want to put a hole in? I don't know if the guy who pulled the trigger knew the rules, but that still doesn't change the fact that he pulled the trigger of a gun that was aimed at someone's head. He deserved exactly what he got. And, well, his dead friend was just as stupid. Sounds to me like just some more chlorination of the gene pool.