A couple of flags early on:
7 Sections 133C(3) and (4) are in the following terms:
(3) The Minister may cancel a visa held by a person if:
(a) the Minister is satisfied that a ground for cancelling the visa under section 116 exists; and
(b) the Minister is satisfied that it would be in the public interest to cancel the visa.
Note: The Minister’s power to cancel a visa under this subsection is subject to section 117 (see subsection (9) of this section).
(4) The rules of natural justice, and the procedures set out in Subdivisions E and F, do not apply to a decision under subsection
...
THE RELEVANT STATUTORY PROVISIONS
18 We have set out ss 116(1)(e)(i) and 133C(3) above. The elements of s 133C(3) should be noted: a power or a discretion to cancel a visa (“may cancel a visa”) held by a person; if the Minister is satisfied that a ground for cancellation under s 116 exists; and (separately and in addition) the Minister is satisfied that it would be in the public interest to cancel the visa.
19 The elements of s 116(1)(e)(i) should be noted. As with ss 133C(3)(a) and (b), the power in s 116 is engaged by or conditioned upon the Minister being satisfied of certain matters, here satisfied of the matters in para (e)(i). Those matters are, relevantly for present purposes, that the presence of the visa holder in Australia is or may be, or might be, a risk to the health, safety or good order of the Australian community or a segment of it.
The state of “satisfaction”
20 Thus it is not the fact of Mr Djokovic being a risk to the health, safety or good order of the Australian community; rather it is whether the Minister was satisfied that his presence is or may be or would or might be such a risk for the purposes of s 116(1)(e)(i), through s 133C(3).
21 The satisfaction of the Minister is not an unreviewable personal state of mind. The law is clear as to what is required. If, upon review by a court, the satisfaction is found to have been reached unreasonably or was not capable of having been reached on proper material or lawful grounds, it will be taken not to be a lawful satisfaction for the purpose of the statute. In such a case the precondition for the exercise of the power will not exist and the decision will be unlawful and will be set aside. That is, the lawful satisfaction is a jurisdictional precondition, a form of jurisdictional fact, for the exercise of the power or discretion: Minister for Immigration and Multicultural Affairs v Eshetu [1999] HCA 21; 197 CLR 611 at 651 [131] and the cases cited at footnote 109.