Having now skimmed them, para [104] probably is the most instructive bit for people who are concerned about how this decision could have been reached:
Thus, as I said a couple of days ago, "There is a vast body of common law that reduces the necessary factual basis for a decision sufficient to survive a judicial review application to an extraordinarily low threshold of plausibility and logic."Parliament has made clear in s 116 that the Minister may cancel a visa if he or she is satisfied that presence of its holder in Australia may be a risk to the health or good order of the Australian community. The Minister reached that state of satisfaction on grounds that cannot be said to be irrational or illogical or not based on relevant material. Whether or not others would have formed that state of satisfaction and the state of satisfaction as to the public interest is a consideration not to the point. The relevant states of satisfaction were of matters which involved questions of fact, projections of the future and evaluations in the nature of opinion. As Gummow J said in Eshetu 197 CLR at 654 [137]: “where the criterion of which the authority is required to be satisfied turns upon factual matters upon which reasonable minds could reasonably differ, it will be very difficult to show that no reasonable decision-maker could have arrived at the decision in question”.