One strand in the “public reason” approach to political justification, stated in a very general form, might go something like this: in the context of disagreement about which shared, public norms to codify and enforce, when actual consensus is not present, the obvious or evident nature of important, relevant objective reasons, the recognition of which would rationally tend to lead to consensus (this situation constituting a certain kind of hypothetical consensus) suffices to make for permission to enforce. One way to characterize this general approach is by saying that there is a “disagreement problem” specific to the relevant context that is “solved” by taking steps toward consensus (with enough truth in it) on the matter as against simply seeking the truth. Here is a specific proposal along these lines, a first shot in the right direction with this kind of approach, to play with and evaluate:
Group G is permitted to enforce norm N on the members of G iff (a) no members of G reject, on the basis of quite strong and evident reasons, G enforcing N and (b) no members of G fail to reject, on the basis of ignorance of strong and evident reasons, G enforcing N.
I’ll note a couple of things about this proposal/formulation and what I’m trying to do with it.
First, with Estlund, I’m using the acceptance/rejection/acquiescence attitudinal stances here because belief does not seem most salient. For example, I might believe that G enforcing N is not what G should do here – maybe I think G enforcing N* is quite a bit better and an available alternative – but nevertheless acquiesce in G enforcing N (in a not-super-unreasonable way) and this seems to be what matters.
Second, with the two conjuncts here, I’m allowing both (i) passive non-rejection (acquiescence, non-consideration) to do normative work subject to only weak normative conditions (roughly, this stance not being super-unreasonable in anyone) and (ii) rejection to do normative work only when stronger normative conditions (roughly, not being super-unreasonable) are met. This is because it seems that you have to do both of these things in order to solve the problem at hand (roughly, that of achieving normative conditions for fair consensus, the actual achievement of such being unrealistic). At a more intuition-driven level, you need to include these sorts of elements in order for something like a theory of legitimacy (in Estlund’s sense) to do the work that we think it should do.
Third, both conjuncts incorporate a theory of reasonableness that requires some contact with reality (knowledge, correct valuing including the value of basic norms or models of fairness in relevant circumstances). As a result, I’m not so concerned about the extent to which false reasons or conclusions are allowed to do work, though the model is biased against this and might, with more precisification, become more or less thus biased.
Fourth, relatedly, this proposal seems to be different, in many ways that I am not fully tracking right now, from how Estlund sometimes seems to think of public reason simply as a response to something like this sort of disagreement (it is certainly quite different from how, in a different mood, he thinks of public reason as a “tolerance response” to certain “moral worldview” beliefs that might well be and often are false or quite unreasonable). What jumps out at me is that, by rejecting the religious tolerance model and incorporating objective normative reasons (facts, ignorance of them) in the relevant benchmarks of reasonableness, my approach is much less truth-phobic and much less concerned to accommodate false and unreasonable religious or similar moral-worldview beliefs (i.e., in objections/rejections or reasons for such).