The converse of the separation of powers is the decision of the High Court in "Boilermakers' Case" in 1956, that Chapter III courts cannot be invested with anything "other than" judicial power. To some extent the rigour of the separation of powers doctrine was softened by the Court's subsequent acceptance that judges could, constitutionally, be assigned functions in their "personal" capacity as judges rather than as members of a Chapter III court. But this raised the question of which such functions were compatible with the simultaneous holding of Federal judicial office. The answers offered by the Court have been controversial and involved some very fine distinctions: for instance, it has held that a power to authorise telephone interceptions "is" compatible, while a power to make recommendations concerning the protection of land which might be of heritage significance to Aboriginals "is not" compatible. The most striking application (and extension) of this "incompatibility" doctrine, however, has involved the Supreme Court of the State of New South Wales, a court that may be invested with Federal jurisdiction. "Kable v Director of Public Prosecutions" (1996) concerned a criminal law passed by the New South Parliament and directed at a single named individual (somewhat in the manner of a Bill of attainder).