A key motivation behind procedural liberalism is that society would descend into anarchy if everyone flouted the law whenever they disagreed with it. We generally want others to respect the rule of law, no matter whether they personally agree with the particular laws in question. We wish to condemn religious extremists who bomb abortion clinics, no matter their righteous motives. So it would be hypocritical to make an exception only for ourselves, or the causes we happen to believe in. As stated, this criticism is overly crude, and leaves open an easy answer for the radical: they do not claim moral permission to break whatever laws they like. Rather, they think we should oppose unjust laws – a perfectly universalizable claim – and they implement this general principle as best they can, in relation to the particular laws they believe to be unjust.
We may grant the radical the desirability of universal perfect compliance with the rule ‘flout all and only unjust laws’. But it is not realistic to think that humble mortals are capable of following this rule perfectly. As has long been recognized in relation to naïve utilitarianism, the direct and deliberate pursuit of such a difficult goal is likely to backfire terribly. So we need to take human error into account when assessing moral guidelines, and hence specify them in terms of the decision-procedure that one is to attempt to follow, without presupposing perfect success. I suggest that when we do this, radicalism is no longer universalizable. At least, the decision-procedure ‘flout all and only laws that you consider to be unjust’ is plainly indefensible, since it would serve to legitimize “righteous” terrorism such as abortion clinic bombings. We cannot universalize a decision procedure that would allow one to act coercively whenever they believe it would do the most good. So we cannot rationally act in such a way ourselves; we must first subject our proposals to the same tests that we would reasonably demand of others. This raises the question: can radicals base their decisions on a more reliable procedure?