It shall be lawful for the legislature for the time being of Western Australia to make laws altering or repealing any of the provisions of the scheduled Bill in the same manner as any other laws for the good government of that colony, subject, however, to the conditions imposed by the scheduled Bill on the alteration of the provisions thereof in certain particulars until and unless those conditions are repealed or altered by the authority of that legislature.
The scheduled Bill, being the Constitution Act 1889 ("the 1889 Act"), became law on the proclamation of the Royal Assent on 21 October 1890. Section 2 established a Legislative Council and a Legislative Assembly, and provided (and still provides) that
it shall be lawful for Her Majesty, by and with the advice and consent of the said Council and Assembly, to make laws for the peace, order, and good Government of the Colony of Western Australia and its Dependencies
The Act included provisions dealing with the qualification of members of the Assembly and the Council (ss. 18, 23, 25, 29), and with the qualification of electors of the two Houses (ss. 39, 53). Section 73 provided:
The Legislature of the Colony shall have full power and authority, from time to time, by any Act, to repeal or alter any of the provisions of this Act. Provided always, that it shall not be lawful to present to the Governor for Her Majesty's assent any Bill by which any change in the Constitution of the Legislative Council or of the Legislative Assembly shall be effected, unless the second and third readings of such Bill shall have been passed with the concurrence of an absolute majority of the whole number of the members for the time being of the Legislative Council and the Legislative Assembly respectively. Provided also, that every Bill which shall be so passed for the election of a Legislative Council at any date earlier than by Part III. of this Act provided, and every Bill which shall interfere with the operation of sections sixty-nine, seventy, seventy-one, or seventy-two of this Act, or of Schedules B., C., or D., or of this section, shall be reserved by the Governor for the signification of Her Majesty's pleasure thereon.
Part III provides for the substitution of a fully elective Legislative Council for the original nominee Council. Section 73 was substantially amended by the Acts Amendment (Constitution) Act 1978 but the amendment is not material to this action. I will continue to refer to the section, now 73(1), as it stood before the amendment.