The power to issue public health orders under s 7 of the Public Health Act 2010 (NSW) is very broadly construed, the principle of legality has limited application where the Act expressly contemplates restriction of movement, and the administrative/legislative distinction is irrelevant to validity.
The full text is available to signed-in members, including the 72 later cases that cite this judgment.
13 of the 72 citing cases carry a classified treatment. How each court treated it is available to signed-in members.