I see where you're going with the curved-tire theory. If his tires were relatively new then his contact patch would be pretty small anyway. Having said thta, if his tires were old then there could be a wider, flatter bald area that could make hydroplaning more likely. Still, I can't even think of 14 traffic laws he could have broken (assuming he didn't flee). Speed, helmet, insurance, registration, maybe the bike was stolen, no eye protection... I'm running out already.