I've just been struck by the obviousness of this principle: It would be unjust for you to be punished for something that someone else made you do.
But it wouldn't be unjust for you to be punished for freely doing something seriously morally wrong. Hence, it is impossible for someone to make you freely do something seriously morally wrong. But if compatibilism is true, then it is possible for someone to make one freely do something seriously wrong: a powerful being could produce a state of the universe long before one's conception that determines one to do that wrong. (In principle a compatibilist could insist--as Ayer did--that it takes away one's freedom when an agent determines one to act a certain way. But this cannot be maintained. Whether I'm free shouldn't depend on ancient history.)