Part of the confusion, I believe is occurring because the administration wanted bin Laden dead, but international law being what it is (see der Spiegel), is questioning the legality of the kill. I think this is why they first said bin Laden had a gun, so it was okay to kill him. Then the truth starts coming out and they have to retract some of what was said at first.
If he didn’t have a gun or any weapon was it legal to kill him? He must have been trapped being on the upper floor. Why not bring him in alive. In our law even the worst criminal isn’t shot down like a dog when they are unarmed and have no where to go. I wonder what it may have been that they were afraid he would reveal. We should have taken him in and interrogated the stuffing out of him to get any possible information that we could have gotten out of him. A trial would have been justice drawn out and savored providing that he ultimately was put to death like Saddam H and Nazi war criminals. Killing him instantly was much easier for him than going through a long drawn out trial before being put to death would have been.