Australian Constitution - Section 75 - Original jurisdiction of High Court
In all matters-
(i.) Arising under any treaty:
(ii.) Affecting consuls or other representatives of other countries:
(iii.) In which the Commonwealth, or a person suing or being sued on behalf of the Commonwealth, is a party:
(iv.) Between States, or between residents of different States, or between a State and a resident of another State:
(v.) In which a writ of Mandamus or prohibition or an injunction is sought against an officer of the Commonwealth:
the High Court shall have original jurisdiction.