468 Melbourne University Law Review [Vol 40:456 IV S TAT E L E S S N E S S A N D C I T I Z E N S H I P L AW I N A U S T R A L IA The Australian Constitution does not confer plenary power with respect to ‘nationality’ or ‘citizenship’ on the Commonwealth Parliament, but rather confers plenary power with respect to the related topics of ‘immigration’65 and ‘aliens’.66 As the High Court of Australia has observed, the Constitution therefore ‘does not identify any specific criterion for membership of the Australian body politic or for the withdrawal of that membership.’67 Hence, constitutional adjudication concerning the limits and constraints on parliamentary sovereignty in relation to citizenship law has centred on the extent to which there may be a concept of constitutional non-alien ---- that is, the notion that a person may be outside the Commonwealth’s aliens power because of a qualitative connection with Australia regardless of statutory entitlement to citizenship.68 In Singh v Commonwealth,69 the High Court rejected the plaintiff ’s argument that birth in Australia necessarily accorded her the status of non-alien, and thus a constitutional nationality that could not be displaced by legislation.70 Indeed, although the High Court continues to insist that the phrase ‘alien’ ‘involves a constitutional concept’ to be interpreted by the Court,71 and hence that ‘Parliament cannot, simply by giving its own definition of ‘‘alien’’, expand the power … to include persons who could not possibly answer the 65 Australian Constitution s 51(xxvii) refers to ‘immigration and emigration’. 66 Australian Constitution s 51(xix) refers to ‘naturalization and aliens’. See generally Sangeetha Pillai, ‘Non-Immigrants, Non-Aliens and People of the Commonwealth: Australian Constitutional Citizenship Revisited’ (2013) 39 Monash University Law Review 568. 67 Re Patterson; Ex parte Taylor (2001) 207 CLR 391, 409 [41] (Gaudron J). 68 For a thorough discussion of the history of constitutional adjudication, including in relation to the notion of ‘non-immigrant’, see Michelle Foster, ‘An ‘‘Alien’’ by the Barest of Threads’ ---The Legality of the Deportation of Long-Term Residents from Australia’ (2009) 33 Melbourne University Law Review 483, 489--503. 69 (2004) 222 CLR 322. 70 Ibid 340--2 [29]--[33] (Gleeson CJ), 399--400 [203]--[205] (Gummow, Hayne and Heydon JJ), 419 [272] (Kirby J). See also Michelle Foster, ‘Membership in the Australian Community: Singh v The Commonwealth and its Consequences for Australian Citizenship Law’ (2006) 34 Federal Law Review 161. 71 Re Minister for Immigration and Multicultural Affairs; Ex parte Te (2002) 212 CLR 162, 205 [159] (Kirby J).