State of Tasmania v Johnston

The High Court of Australia heard an appeal from the Supreme Court of Tasmania in the matter of *State of Tasmania v Johnston*. The dispute concerned the validity of a notice issued by the State of Tasmania under section 11(1) of the *Public Health Act 1997* (Tas) requiring Mr. Johnston to undertake a period of quarantine. Mr. Johnston challenged the lawfulness of this notice.

The central legal issue before the High Court was whether the notice issued under section 11(1) of the *Public Health Act 1997* (Tas) was invalid for failing to comply with the requirements of section 11(2) of that Act, which stipulated that such a notice must specify the period of isolation or quarantine. The Court also considered whether, if the notice was invalid, it could be cured by subsequent events or actions.

The Court held that section 11(2) of the *Public Health Act 1997* (Tas) imposed a mandatory requirement that a notice of isolation or quarantine must specify the period of isolation or quarantine. As the notice issued to Mr. Johnston did not specify a period, it was invalid. The Court rejected arguments that the notice could be validated by subsequent events, such as Mr. Johnston's subsequent compliance with quarantine directions, finding that the invalidity of the notice at the time of its issue could not be retrospectively cured.

The High Court allowed the appeal, setting aside the order of the Supreme Court of Tasmania and remitting the matter to the Supreme Court for further consideration.