Benbrika v Minister for Home Affairs

In this matter before the High Court of Australia, the applicant, Mr. Benbrika, an Algerian and Australian citizen, challenged a determination by the Minister for Home Affairs that he had ceased to be an Australian citizen. This determination was made under section 36D of the *Australian Citizenship Act 2007* (Cth), which allows the Minister to make such a determination if a person has been convicted of a terrorism offence under Chapter 5.3 of the *Criminal Code* (Cth) and sentenced to at least three years imprisonment, and the Minister is satisfied the conduct demonstrates a repudiation of allegiance to Australia. The applicant had been convicted of such offences and sentenced accordingly.

The central legal issue before the Court was whether section 36D of the *Australian Citizenship Act 2007* (Cth), like section 36B of the same Act which had previously been held invalid in *Alexander v Minister for Home Affairs*, was contrary to Chapter III of the Constitution. Specifically, the Court had to determine if section 36D improperly conferred upon the Minister the exclusively judicial function of punishing criminal guilt, thereby infringing the separation of powers. This involved considering whether Chapter III prohibits the Commonwealth Executive from exercising the power to punish criminal guilt when a court has already adjudged that guilt, and whether any exception exists for the involuntary deprivation of citizenship as a form of punishment following a conviction.

The High Court, applying the principles established in *Alexander*, concluded that section 36D of the *Australian Citizenship Act 2007* (Cth) was invalid. The Court reasoned that the power to determine that a person ceases to be an Australian citizen under section 36D, in circumstances where that cessation is predicated on a criminal conviction and sentence for a terrorism offence, constitutes the exercise of the judicial function of punishing criminal guilt. The Court found that this power, when vested in the Minister, transgressed the constitutional prohibition against the repository of executive power exercising the judicial power of the Commonwealth, particularly in the context of punishing criminal guilt already adjudicated by a court.

Consequently, the High Court answered the questions stated for its opinion. It declared that section 36D of the *Australian Citizenship Act 2007* (Cth) is invalid in its operation in respect of the applicant because it reposes in the Minister for Home Affairs the exclusively judicial function of punishing criminal guilt. The Court further declared that the applicant remains an Australian citizen and ordered that the respondents pay the costs of the special case.