What was terra nullius doctrine?

Terra nullius doctrine, looked at strictly as a piece of legal reasoning, classified the Australian colonies as 'settled' rather than 'conquered' or 'ceded' British possessions. That technical classification mattered because British common law treated each category differently: in settled colonies the existing inhabitants had no recognised law of their own and English law applied automatically from the moment of British arrival, while in conquered or ceded colonies the pre-existing local law continued until the Crown displaced it.

Nineteenth-century case law hardened the classification. Forbes CJ of the NSW Supreme Court in R v Murrell (1836) held that British law applied to Aboriginal people because the colony was settled, and that no parallel Aboriginal legal system was recognised. The Privy Council in Cooper v Stuart (1889) sealed the doctrine for the next century, describing NSW as 'a tract of territory practically unoccupied, without settled inhabitants or settled law' at the time of British annexation. Colonial property law flowed directly from that classification: all land was treated as Crown land available for Crown grant, sale, or reservation, with no native interest surviving the assertion of sovereignty.

The 1992 Mabo decision attacked the doctrine at the level of legal reasoning rather than the historical record. Justice Brennan held that the proposition that the inhabitants of a settled colony lacked rights recognisable in law was based on 'a discriminatory denigration of indigenous inhabitants, their social organisation and customs', and that it could no longer stand in modern Australian common law. Crucially, the High Court did not question the validity of British sovereignty (an act of state that domestic courts cannot review) but did reject the doctrinal consequence that sovereignty extinguished all pre-existing land interests. Native title was held to survive in the common law where Aboriginal or Torres Strait Islander people had maintained their traditional connection to country and their rights had not been validly extinguished by Crown grant or inconsistent legislation.

The post-Mabo doctrinal landscape has been built up through later litigation and statute. The Native Title Act 1993 codified Mabo and created the National Native Title Tribunal, the Federal Court native title process, and statutory rules for validating past grants. Wik Peoples v Queensland (1996) ruled that pastoral leases did not necessarily extinguish native title, prompting the Native Title Amendment Act 1998. Yorta Yorta v Victoria (2002) clarified that native title requires continuous observance of traditional law and custom since sovereignty. Northern Territory v Griffiths (the Timber Creek decision, 2019) set the framework for compensation when native title has been extinguished. Each of these cases works within the doctrinal architecture that the rejection of terra nullius made possible.