The plaintiffs' principal submission was that the Cancellation of Registration Act is invalid because it is an exercise of the judicial power of the Commonwealth or, alternatively, because it involves an interference with the judicial power. The Cancellation of Registration Act, if valid, abrogates the function which would otherwise have been performed by this Court in the proceedings pending in the Court pursuant to the Federation's notice of motion for the orders nisi previously mentioned. It is for this reason that the plaintiffs contend that the Cancellation of Registration Act is an exercise of judicial power and that it amounts to an interference with this Court's exercise of the power, an exercise which had been invoked by the Federation before that Act became law. The plaintiffs pointed to the statement in Re Ludeke [4] : "that the deregistration of an organization under the Conciliation and Arbitration Act can be achieved either by the exercise of judicial power or by the exercise of administrative power". But this statement, as its context demonstrates, does no more than assert, in accordance with the authorities, that Parliament may authorize deregistration under the Conciliation and Arbitration Act by the exercise of either judicial or administrative power. The statement has nothing to say about the deregistration of an organization by means of a legislative act, which involves no determination by a court or tribunal as to the conduct of the organization, outside the procedure for deregistration established by the Conciliation and Arbitration Act. Even if registration under that Act amounts to an acceptance or endorsement that the organization is a fit and proper organization to participate in the system of conciliation and arbitration, there is nothing in the nature of participation in that system or in deregistration which makes deregistration uniquely susceptible to judicial determination, as the discussion in Re Ludeke reveals. Nor is there anything in the nature of deregistration which makes it unsusceptible to legislative determination. Just as it is entirely appropriate for Parliament to select the organizations which shall be entitled to participate in the system of conciliation and arbitration, so it is appropriate for Parliament to decide whether an organization so selected should be subsequently excluded and, if need be, to exclude that organization by an exercise of legislative power.