On 11 November 2010, the High Court of Australia handed down a landmark Australian Immigration decision in Plaintiff M61/2010E and M69 of2010 v Commonwealth of Australia, declaring that it was an error of law for a person conducting a review of a refugee status assessment as part of an "offshore processing regime" to fail to treat provisions of the Australian Migration Act 1958 and Australian Immigration decisions of Australian courts as binding.

The Court also held that the applicants who arrived at Christmas Island claiming refugee status were denied procedural fairness in the review of the assessment of their claims.

The High Court of Australia summarised the Australian Immigration decision as follows:

“Under the Migration Act, each became an "unlawful non-citizen" and by the operation of section 46A(1) could not make a valid application for a protection visa. The Minister had power to waive the operation of section 46A(1), or grant a visa, if it was in the public interest to do so. During the plaintiffs' detention, officers of the Department of Immigration and Citizenship made assessments of each plaintiff's refugee status and concluded that neither was a person to whom Australia owed protection obligations. An Independent Merits Review of each of those decisions conducted by contractors of the Department reached the same conclusion.

Each plaintiff argued before the High Court that he was not afforded procedural fairness during the assessment or review process, and that the persons conducting the assessment and review erred in law by not treating themselves as bound by relevant provisions of the Migration Act and relevant decisions of Australian courts. The plaintiffs argued that the processes were a part of the exercise of the Minister's powers under the Migration Act.

In a unanimous decision the Court held that because the Minister has decided to consider exercising powers under the Migration Act in every case where an offshore entry person claims to be owed protection obligations, the assessment and review inquiries adopted in respect of such offshore entry persons are therefore steps taken under and for the purposes of the Migration Act. Those making the inquiries were therefore bound to act according to law and to afford procedural fairness to the plaintiffs.”

As a result of the High Court’s decision, it is now open to all persons who have had their refugee claims rejected, to seek judicial review in Australian Courts to ensure that decision was lawful and made in accordance with Australian immigration law. It is understood that this decision may potentially affect more than 1000 persons currently held at offshore processing centres.

The Australian Immigration Minister, Chris Bowen, has responded to the High Court ruling confirming that the Australian Government respects the decision of the High Court of Australia as the final authority on the lawful interpretation of Australian immigration law but noted that the Australian Government would not rule out a legislative response to the Courts decision.