The Constitution of Equality provides a philosophical account of the moral foundations of democracy and of liberalism. It shows how democracy and basic liberal rights are grounded in the principle of public equality, which tells us that in the establishment of law and policy we must treat persons as equals in ways they can see are treating them as equals. The principle of public equality is shown to be the fundamental principle of social justice. This account enables us to understand the nature and roles of adversarial politics and public deliberation in political life. It gives an account of the grounds of the authority of democracy. It also shows when the authority of democracy runs out. Christiano shows how the violations of democratic and liberal rights are beyond the legitimate authority of democracy, how the creation of persistent minorities in a democratic society, and the failure to ensure a basic minimum for all persons weaken the legitimate authority of democracy.