2017] Citizenship Stripping Laws in the UK, Canada and Australia 5 concerns.9 While the recent repeal of these powers in Canada signifies a partial retreat from this trend, there is no evidence to date of this approach being mirrored in the UK, Australia or other countries. The increased tendency to invoke citizenship stripping as a national security tool raises the question of whether citizenship deprivation can ever be considered justified on security grounds. This question has been explored in a number of recent commentaries,10 and we do not address it in this article. Our focus is squarely on whether recent examples of such laws in the comparator countries have served as an effective means by which to pursue their stated goals. This approach fills a meaningful gap in recent scholarship on citizenship stripping. Most existing work is directed towards one of two ends: exploring normative questions about how denationalisation affects the value of citizenship as a status,11 or analysing some aspect of citizenship deprivation within a 9 In the last two years, several countries have enacted citizenship stripping laws as a response to security threats, including Austria, Azerbaijan, Belgium and The Netherlands: see, eg, Sangeetha Pillai and George Williams, ‘Twenty-First Century Banishment: Citizenship Stripping in Common Law Nations’ (2017) 66 International and Comparative Law Quarterly 521, 522 n 8, citing: Code de la Nationalité Belge 1984 [Belgian Nationality Code 1984] art 23(1)(ii); Staatsbürgerschaftsgesetz 1985 [Nationality Act Austria] § 33(2); Azad Hasanli, ‘Azerbaijanis Engaged in Terrorist Activity to Lose Citizenship’, Trend News Agency (Baku, 4 December 2015) <https://en.trend.az/azerbaijan/society/2465160.html>, archived at <https://perma.cc/D678SBT5>; Netherlands Nationality Act (Netherlands) art 14(2)(b) [Olivier Vonk trans]. In this period, other countries have also resumed utilisation of citizenship stripping laws. For example, in Denmark, s 8B of the Consolidation Act No 422 of 7 June 2004 (Consolidated Act on Danish Nationality) [Bertel Haarder and Oluf Engberg, Ministry of Refugee, Immigration and Integration Affairs trans, 7 June 2004] was employed for the first time to deprive Said Mansour of his Danish citizenship: ‘Denmark Strips Man of Citizenship over “Terror Links”’, Al Jazeera (Online, 11 June 2016) <www.aljazeera.com/news/2016/06/denmark-strips-man-citizenshipterror-links-160611080713219.html>, archived at <https://perma.cc/CTJ8-JQAD>. On 8 June 2016, the Supreme Court of Denmark upheld the decision to revoke Mansour’s citizenship: see Prosecution Service v T (Højesterets Dom [Supreme Court of Denmark], Case No 211/2015, 8 June 2016). 10 See, eg, Matthew J Gibney, ‘Should Citizenship Be Conditional? The Ethics of Denationalization’ (2013) 75 Journal of Politics 646; Christian Joppke, ‘Terror and the Loss of Citizenship’ (2016) 20 Citizenship Studies 728; Patti Tamara Lenard, ‘Democracies and the Power to Revoke Citizenship’ (2016) 30 Ethics and International Affairs 73. 11 See, eg, Lucia Zedner, ‘Security, the State, and the Citizen: The Changing Architecture of Crime Control’ (2010) 13 New Criminal Law Review 379; Shai Lavi, ‘Citizenship Revocation as Punishment: On the Modern Duties of Citizens and Their Criminal Breach’ (2011) 61 University of Toronto Law Journal 783; Rainer Bauböck and Vesco Paskalev, ‘Cutting Genuine Links: A Normative Analysis of Citizenship Deprivation’ (2015) 30 Georgetown Immigration Law Journal 47; Patrick Sykes, ‘Denaturalisation and Conceptions of Citizenship in the “War on Terror”’ (2016) 20 Citizenship Studies 749. Advance Copy