Australia, High Court of Australia, Palmer v The State of Western Australia, 24 February 2021

As set out by Kiefel CJ and Keane J, s.92 may be understood to preclude laws which burden freedom of interstate trade, commerce and/or intercourse, where the burden cannot be justified as proportionate to purpose of the law. Therefore, restrictions may be justified where they go no further than is reasonably necessary to achieve a legitimate object (where there is no alternative effective measure – which has less restrictive effects on the freedom – available to achieve the same object). They stated that there was no doubt that a law restricting movement of persons is suitable for the purpose of preventing persons with Covid-19 bringing the disease into the community. In terms of whether there was an alternative method, they agreed with the defendants in that the power to prohibit entry should not be read down so as to accommodate an undefined level of risk. Therefore, they held that there was no effective alternative. They also accepted that although the restrictions were severe, it cannot be denied that the importance of the protection of health and life justified the severity of the measure.

Gageler J stated that a differential burden on interstate intercourse, which results from an exercise of power of direction, is justified where it is reasonably necessary when compared to the range of potential exercises of the power. Gageler concluded that, in this case, such a differential burden was not discriminatory, nor was it protectionist.

Gordon J stated that the restrictions on the freedom did not impose an unjustified differential burden, nor was it discriminatory.

Edelman J stated that the purpose of public health could be used to justify even deep and wide burdens of freedoms, agreeing that the measures were justified.