@snood,
I don't think it's anything to do with what's been rumoured. Having people piss all over you is not illegal and if that were proved to be true it would just be a minor embarrassment. Cameron stayed prime minister after it was alleged he'd put his cock in a dead pig's mouth, although he was the butt of many jokes.
What Putin has is something that could potentially put Fart in jail, and considering his penchant for bursting into the changing rooms of 15 year old beauty pageant contestants, I imagine it's something like that.