There was no legal definition of the British Empire and it possessed no explicit constitutional meaning. The empire was diverse and incoherent and terminology was not very clear. The terms ‘colony’, ‘dominion’, ‘possession’, ‘plantation’, and other expressions were used in different ways at different times. Indeed, an anti-formalist attitude tended to prevail – often eschewing formal law in favour of informal assurances, customs, and conventions. There was no attempt to establish a uniform legal code. And the sovereignty of the Parliament in London was only one of many types of sovereignty that existed. Much of the British Empire lent itself to a more pluralistic type of sovereignty – one that was divided, shared and indeterminate. Indeed, it was likely that power was the only unifying factor underlying the empire, aided by British naval supremacy, and the fact that, in the nineteenth century, global communications were predominantly in British hands. However, that power could not be derived from a unified, coherent account of legal and political sovereignty. And power by itself lacks legitimacy – it must be validated by something else – which is where sovereignty becomes relevant, in providing that grounding. Yet, the claims of sovereignty made by the empire were often mutually self-contradictory.

The modern state of New Zealand was founded on the signing of the Treaty of Waitangi between the British Crown and indigenous Maori tribes. New Zealand’s partly uncodified, partly unwritten constitution is thus structured around questions of indigenous rights and the treaty relationship between the Maori and the Crown. This chapter examines how and why the Treaty and indigenous rights play a fundamental role in New Zealand’s constitutional system, and it uses the example of New Zealand to challenge conventional understandings as to what counts as a “constitution.”