Liberty of conscience plays two roles throughout Rawls’s work. First, it is among the most important basic liberties that Rawls endorses in A Theory of Justice, Justice as Fairness, Political Liberalism, and Law of Peoples. Second, and more broadly, the idea liberty of conscience helps to explain the aim of Rawls’s entire philosophical project. Let us explore these two roles in turn.

Liberty of conscience is one of the first liberties Rawls defends as part of his first principle of justice, for “each person is to have an equal right to the most extensive scheme of equal basic liberties compatible with a similar scheme of liberties for others” (TJ 53). One of these maximally extensive liberties is liberty of conscience. Because liberty of conscience is one of our “fixed points” among considered judgments, any good theory of justice must account for it (TJ 181). The argument for liberty of conscience in TJ §33 runs roughly as follows: behind the veil of ignorance, the parties are unaware of their conception of the good. Accordingly, they are unaware of their moral and religious views (TJ 181). Rawls also argues that parties do not know which religions are present in their society or which religions are in the majority or minority (TJ 181). Therefore, the parties, knowing how important their conceptions of the good might be to them, cannot take the chance that their religion will come out on top if principles of justice favor a particular religion (TJ 181). Consequently, the parties will guarantee liberty of conscience up to the point where it produces public disorder: “liberty of conscience is to be limited only when there is a reasonable expectation that not doing so will damage the public order which the government should maintain” (TJ 186; also see JF 104).