I shall begin with a riddle, in fact three riddles:

1. 1 What sort of interest in land is held as an estate in fee simple but is inalienable?

2. 2 What sort of interest in land is held by a registered proprietor who has no power to make decisions relating to it, except with the consent of another, and who must act at the direction of that other?

3. 3 What sort of interest in land does not carry with it ownership of minerals but can preclude mining thereon?

The answer to each of these questions is — Aboriginal land under the Aboriginal Land Rights (Northern Territory) Act 1976 (Cth) (“the Land Rights Act”).

The purpose of this paper is not to trace the course of judicial history in this country, from the robust assertion of the Privy Council that the colony of New South Wales “consisted of a tract of territory practically unoccupied, without settled inhabitants or settled law, at the time when it was peacefully annexed to the British dominions” to the judgment of Blackburn J in Milirrpum v Nabalco Ply Ltd.

In any field of law . . . there may arise the rare “landmark” case in which a court, usually a final appellate court, concludes that the circumstances are such as to entitle and oblige it to reassess the content of some rule or set of rules in the context of current social conditions, standards and demands and to change or reverse the direction of the development of the law.

When the 1983 amendments were made to the national companies securities legislation, it was stated in the accompanying explanatory memorandum that one of the purposes of the new provisions was to “abolish the doctrine of ultra vires” — an ambitious aim given the tenacity of the doctrine despite widespread criticism on many grounds, perhaps best summed up in the comment, “[u]ltra vires was the expression of a social policy that failed.”

Of course, it has now been realised that the 1983 amending Act did not achieve its stated purpose. It may have achieved a partial elimination of the doctrine but it has left a large area for its continued operation in a different form and in some respects has opened new opportunities for development.

These aspects are explored below but it should be noted here that one curious side of the new provisions is that no explanation was offered of the defects in the previous statutory provisions, ss 67-68 of the Companies Act (Cth) (“the Act”) and its forerunner, s 20 of the State uniform companies legislation, nor was it explained how the new ss 67-68 were intended to remedy those defects. The new regime was simply offered as a better general solution to the ultra vires problem. Unfortunately, in this case, it is not the final solution.

A number of questions concerning the construction and application of section 57 of the Constitution have now been determined by the High Court. The purposes of this note are to examine critically some implications of these answers and to direct attention to some other technical questions that could arise in the future. The special interest of the writer in these matters arises from the fact that he was closely involved in the preparation of documents in relation to the double dissolutions of 1974 and 1975 and the joint sitting of 1974.

It is not within the purposes of this article to discuss generally the extent to which the Governor-General may be entitled to exercise a personal judgment or discretion in granting or refusing a double dissolution. That is a matter of constitutional propriety rather than the justiciable constitutional law with which this article is concerned.