The interpretation in Crosby v Kelly of s 9(3) of the Jurisdiction of Courts (Cross-vesting) Act 1987 (Cth) as a law of the Commonwealth for the purposes of s 76(ii) of the Constitution has had significant consequences for the Australian Judicature, including, most notably, the establishment of the Federal Court's defamation jurisdiction. This article considers and tests the conceptual underpinnings of Crosby v Kelly's reasoning. While the Commonwealth Parliament undoubtedly has legislative power to confer jurisdiction on the Federal Court with respect to defamatory publications in the territories, this article argues that there is considerable doubt that, as a matter of statutory construction, that power was exercised in the enactment of s 9(3). If the Federal Court's jurisdiction cannot be sustained under s 9(3), this article argues that there would not appear to be a clear and established basis for the Federal Court to hear and determine defamation proceedings.