That is, they think all of their decisions were preordained, and then use this to claim that they can’t be held responsible for anything they do.
Tell them they should have factored the consequences into their predetermined behavior.
They should also understand why consistent enforcement is necessary to prevent others from making the same preordained decision.
Even if the choice is only illusory, it’s indistinguishable from free will in every other respect… So we will treat it as such