Page:NZYQ v Minister for Immigration, Citizenship and Multicultural Affairs.pdf/18

Gageler CJ Gordon J Edelman J Steward J Gleeson J Jagot J Beech-Jones J

and immunities under the law differ from those of a non-alien in a number of important respects.

The third principle was that the relevant difference between a non-alien and an alien for the purposes of Ch III "lies in the vulnerability of the alien to exclusion or deportation". The plurality in Lim observed that this vulnerability flows from both the common law and the Constitution, referring also to matters of territorial sovereignty and international law.

Adherence to these background principles led in Lim to a formulation of constitutional principle which provided the criterion to determine the validity of the sections of the Migration Act impugned in that case. That constitutional principle was formulated in the following terms:

"In the light of what has been said above, the two sections will be valid laws if the detention which they require and authorize is limited to what is reasonably capable of being seen as necessary for the purposes of deportation or necessary to enable an application for an entry permit to be made and considered. On the other hand, if the detention which those sections require and authorize is not so limited, the authority which they purportedly confer upon the Executive cannot properly be seen as an incident of the executive powers to exclude, admit and deport an alien. In that event, they will be of a punitive nature and contravene Ch III's insistence that the judicial power of the Commonwealth be vested exclusively in the courts which it designates."

The constitutional principle so formulated and applied in Lim was not disavowed by the majority in Al-Kateb. But the insistence in Lim that the detention