R v MacKellar; Ex parte Ratu

The High Court of Australia considered an application for a writ of prohibition brought by the applicant, Ratu, against the respondent, MacKellar, who was the Minister for Immigration and Ethnic Affairs. The dispute concerned the Minister's decision to refuse to grant Ratu an entry permit to Australia, and the subsequent detention of Ratu. Ratu sought to challenge the lawfulness of his detention and the validity of the Minister's decision.

The central legal issues before the Court were whether the Minister's decision to refuse an entry permit was valid, and consequently, whether Ratu's detention was lawful. Specifically, the Court had to determine if the Minister had properly exercised his discretion under the relevant provisions of the *Migration Act 1958* (Cth) and whether the procedures followed in making the decision and authorising the detention complied with the requirements of natural justice and the *Migration Act*.

The Court, in a joint judgment, found that the Minister's decision to refuse the entry permit was vitiated by a failure to afford Ratu natural justice. The Minister had relied on information concerning Ratu's alleged criminal activities, which Ratu had not been given an opportunity to answer. The Court held that the Minister's power to refuse an entry permit was not unfettered and required adherence to the principles of procedural fairness. As the decision was invalid, Ratu's subsequent detention, which was predicated on that invalid decision, was also unlawful.

The High Court ordered that a writ of prohibition issue, preventing the Minister from acting upon the invalid decision to refuse the entry permit. The Court also declared Ratu's detention to be unlawful.