Meijers Committee standing committee of experts on international immigration, refugee and criminal law According to Article 7 of the European Convention on Nationality (ECN), a State Party may provide for the loss of its nationality in case of ‘conduct seriously prejudicial to the vital interests of the State Party’, unless the person concerned would thereby become stateless. It follows that deprivation of citizenship on this ground can only take place if the person concerned has dual or multiple nationality. At the same time, the ECN provides that dual nationals are entitled to full citizenship in the state of residence, on an equal footing with mono nationals. This follows from Article 17 (1) ECN which states that ‘nationals of a State Party in possession of another nationality shall have, in the territory of the State Party in which they reside, the same rights and duties as other nationals of that State Party’. As dual nationality is often held by people of migrant origin (see paragraph 2), differential treatment of dual and single nationals often equals indirect differential treatment of racial or ethnic minority groups. Article 5(1) ECN provides that the rules of the States Parties on nationality shall not ‘contain distinctions or include any practices which amount to discrimination, including on the grounds of race, colour or national or ethnic origin’. Article 5(2) ECN adds that the States Parties ‘shall be guided by the principle of non-discrimination between its nationals’, regardless of whether the nationality was obtained at birth or subsequently. The latter provision speaks against laws which provide that only naturalised citizens can be deprived of their citizenship (see further paragraph 7). Articles 8 and 14 ECHR and Article 1 Twelfth Protocol ECHR A prohibition of discrimination is included in Articles 14 ECHR and 1 Twelfth Protocol ECHR. Whereas Article 14 applies to differences in treatment falling within the ambit of the substantive rights and freedoms guaranteed in the Convention,74 Article 1 Twelfth Protocol is applicable to all the rights set forth in the law of the State Party concerned. The ECtHR has already established that the denial or loss of a nationality can affect the rights protected by the Convention, in particular the right to private and family life (Article 8 ECHR).75 The non-discrimination provisions of the ECHR contain open lists of discrimination grounds. The strength of the justification required in cases of presumed discrimination depends on the discrimination ground at stake, as well as the policy area and the right at issue. In a number of cases concerning equal treatment of long-term resident non-nationals, the ECtHR decided that differences in treatment based exclusively on nationality require ‘very weighty reasons’ in order to be justified.76 It has not explained the reasons for this strict test, which makes it difficult to establish whether the same standard applies to differences in treatment between single and dual nationals. We submit that the application of the ‘very weighty reasons’ test 74 E.g. Carson and others/ United Kingdom, ECtHR 16 March 2010, app.no. 42184/05, para 63. Notably Genovese/Malta, ECtHR 11 October 2011, app.no. 53124/09, para 30; Ramadan/Malta, ECtHR 21 June 2016, app.no. 76136/12, paras 84-85; Ghoumid and others/France, ECtHR 25 June 2020, app. nos 52273/16 etc, para 43. 76 E.g. Gaygusuz/Austria, ECtHR 16 September 1996, app.no. 17371/90, para 42; Andrejeva/Latvia, ECtHR (GC) 18 February 2009, app.no. 55707/00, para 87; Ribać/Slovenia, ECtHR 5 December 2017, app.no. 57101/10, para 53. 75 14