Plaintiff M64/2015 v Minister for Immigration and Border Protection

The applicants, identified as Plaintiff M64/2015 and others, sought judicial review of decisions made by the Minister for Immigration and Border Protection concerning their offshore processing and detention. The core of the dispute revolved around the lawfulness of the Minister's decisions to refuse to allow the plaintiffs to enter Australia, despite their arrival on Australian territory, and the conditions of their detention on Manus Island. The matter was heard by the High Court of Australia.

The High Court was required to determine whether the Minister's decisions to refuse entry to the plaintiffs, who had arrived in Australian waters, were valid under Australian law. A further critical issue was whether the detention of the plaintiffs on Manus Island, and the conditions of that detention, were authorised by law, particularly in light of the plaintiffs' status as persons seeking to enter Australia. The court also considered the scope of the Minister's powers and the constitutional implications of offshore processing arrangements.

The Court reasoned that the Minister's power to refuse entry to non-citizens arriving in Australia was not absolute and was subject to the framework established by the *Migration Act 1958* (Cth). It was held that the plaintiffs, by arriving in Australian waters, had effectively entered Australia and were therefore subject to Australian law. The Court found that the Minister's decisions to refuse entry and the subsequent offshore detention arrangements lacked a sufficient statutory basis under the *Migration Act* to be lawful. The constitutional principle that persons physically present within Australia are subject to its laws and entitled to its protection was central to the reasoning.

The High Court ultimately found that the plaintiffs were unlawfully detained and ordered that they be brought to Australia.