Heydon J
76.
compensation, even where such expropriation may be intended to serve a wider public interest."[1]
There is no general principle of Australian constitutional law that legislation which infringes a constitutional limitation on power will be valid so long as it is reasonably appropriate and adapted to a legitimate end within power. There are tests of that kind which operate in quite circumscribed areas. No good reason has been demonstrated to widen those areas. In particular, there is nothing in the language of s 51(xxxi) which supports the test advocated. And since the inquiry into what is "reasonably necessary" is a legislative activity, not a judicial one, it is highly unlikely to be required or permitted by implication in a Constitution, which, like ours, provides for a separation of legislative and judicial power.
There are authorities holding that some laws are outside's 51(xxxi)–laws relating to fines, penalties, taxes, forfeitures, the condemnation of prize, the seizure of enemy alien property, the enforcement of statutory liens, and bankruptcy. But those exceptions exist because the requirement to provide "just terms" is not congruent with those types of law. "To place [a law imposing a penalty for breach of a rule of conduct] within the s 51(xxxi) category would be to annihilate the penalty … and thus to weaken, if not destroy, the normative effect of the prescription of the rule of conduct."[2] There is no incongruity of that kind between the impugned legislation and's 51(xxxi). And it has never been suggested that the examples of "incongruity" turn on inquiries into what is reasonably necessary, or on proportionality analysis. There is no authority supporting the use of proportionality analysis in applying's 51(xxxi).
Further, the Commonwealth's proposed test depends on drawing a difficult distinction between acquisitions which are central or principal aspects of a legislative scheme and those which are merely consequential or incidental. Whatever the merits of that course, the acquisition here is not incidental: it is the fundamental means by which the TPP Act operates and seeks to achieve its goals.
Just terms
In Commonwealth v Huon Transport Pty Ltd, Rich J said[3]:
