The ‘sovereign citizen’ is a contemporary phenomenon increasingly evident in Australia and other jurisdictions. It represents an alternative understanding of constitutions, justice, and authority. It centres on a rhetoric in which adherents assert rights but disclaim responsibilities and deny obedience to national, provincial, or municipal/rural governments when obedience would be inconvenient. The rhetoric involves claims that specific constitutions since the mediaeval period are invalid, with individuals being free of state or corporate authority unless each person chooses to assent. The language seeks to characterise each individual as a sovereign, a self-possessed individual with a legal status equivalent to a state, and lawfully ignoring obligations such as taxation, traffic rules, child support, firearms restriction, and environmental protection. It often features assertions that such obligations are voided through language about an individual’s name or supposed rights to settle disputes through ad hoc ‘juries’ that erase the authority of legislatures, statutes, and formally appointed embodiments of state authority such as judges, police, welfare, and public revenue officials. It also selectively denies the authority of private sector entities such as banks, with sovereign citizens frequently claiming that debts to corporations are not enforceable. The article interrogates the social and conceptual bases of sovereign citizenship in Australia, arguing that the ‘sovereigns’ have a misplaced understanding of the modern legal order and the functioning of constitutions in contemporary liberal democratic states. The rhetoric is incoherent and administratively unpersuasive, reflecting a belief in a past without the ills of the nation state, a world of self-reliant ‘freemen’ and small communities whose legal order was fit for purpose because it was local, trusted, not bureaucratised, and predominantly oral. The article thus offers insights about both the phenomenon and the nature of constitutions.