The doctrine was first clearly applied by the High Court of Australia in the 1985 case of "Hilton v Wells", which involved a challenge to the constitutional validity of certain telecommunications legislation which permitted telephone tapping by way of a warrant, which had to be issued by "a judge". The word "judge" in that piece of legislation was defined to mean a judge of the Federal Court or of the Supreme Court of the Australian Capital Territory, or, in certain circumstances, a judge of the Supreme Court of the Northern Territory or any of the State Supreme Courts. In their majority judgment, Chief Justice Gibbs and Justices Wilson and Dawson acknowledged the difficulty of determining whether a function has been conferred on a court or on a judge of that court, saying that: