Conundrum 11- Who Done It?

I'm sorry for all of those netforum regulars who have already seen this conundrum, but I figure with all the newbies, WHY not ask it again! So here it goes:

MikesFan and Chumby want to both kill the all powerful and great Napolean! All three of them are in the Arizona desert miles from civilization!!! Neither MikesFan or Chumby know that the other wants to kill the great Napolean and Napolean is not aware of their hate or intentions either. The reason they want to kill Napolean is unimportant but lets say they both want to become the new emperor of the L&O forum. Anyway, MikesFan after Napolean is asleep sneaks into his tent and puts a lethal poison in Napolean's canteen. Once he would take a drink of it, he would die instantly. MikesFan sneaks out and goes back to her tent. Not aware of the actions of MikesFan, Chumby sneaks into the tent later that night and pokes a very small hole into the canteen of Napolean (barely noticable). The canteen will run out of water very slow and will not be noticable. All of this takes place because Naplean is a heavy sleeper! When Napolean wakes up in the morning, both MikesFan and Chumby are gone. Napolean takes off to head back to civilization. Napolean does not notice the hole in his canteen! Napolean dies in the middle of the desert due to the lack of water. He never drank the poison!!! Who is guilty? MikesFan had nothing to do with killing him because he never drank the poison. All Chumby did was save him from drinking the poison by poking a whole in the canteen (but remember he didn't know there was poison in there!). So what would you do as prosecutor? I'm dead, get my killer! Hope you enjoy this conundrum!

LOFers have turned off L&O to read this page times.