Western Australia v The Commonwealth

The High Court of Australia considered a dispute between the State of Western Australia and the Commonwealth of Australia concerning the validity of the *Petroleum (Submerged Lands) Act 1967* (Cth). Western Australia challenged the constitutional validity of this Commonwealth legislation, which asserted Commonwealth control over the exploration for and exploitation of petroleum resources in areas adjacent to the Australian coast, including those off the coast of Western Australia.

The central legal issue before the High Court was whether the Commonwealth Parliament had the constitutional power to enact legislation regulating activities in the territorial sea and on the continental shelf beyond the low-water mark, particularly in relation to the exploitation of submerged lands and their resources. This involved an examination of the division of powers between the Commonwealth and the States under the *Australian Constitution*, and the extent of Commonwealth legislative authority in relation to external affairs and the territorial sea.

The Court, by majority, held that the Commonwealth *Petroleum (Submerged Lands) Act 1967* was constitutionally valid. The majority reasoned that the Commonwealth possessed legislative power to regulate activities in the territorial sea and on the continental shelf by virtue of its external affairs power (s 51(xxix) of the Constitution), particularly in relation to international law concerning the continental shelf, and its incidental powers. The Court distinguished between the Crown's proprietary rights in submerged lands and the Commonwealth's legislative power to regulate activities within its territorial jurisdiction, including the continental shelf, for purposes such as defence and international obligations. The decision affirmed the Commonwealth's authority to legislate in these offshore areas, notwithstanding the residual proprietary rights of the States.