absentia, thereby causing an individual not to be able to return to his/her State of (former) nationality. Such deprivation may increase security risks in another State and hinder efforts at enhancing cooperation between States to counter terrorism in line with UN Security Council Resolution 2322 of 201671 and to “co-operate in the promotion of universal respect for, and observance of, human rights and fundamental freedoms for all” under UN General Assembly Resolution 2625 (XXV).72 Wherever possible, the countries of nationality of individuals who become members of armed non-State groups abroad (for example, foreign terrorist fighters) should effectively investigate and prosecute those individuals.73 Failing to hold perpetrators of violations to account may foster a sense of impunity.74 Allegiance to another State or repudiation of allegiance to a Contracting State (Article 8(3)(b)) Where a relevant declaration has been made,75 Article 8(3)(b) allows for an exception to the basic rule that deprivation of nationality may not cause statelessness where either a person “has taken an oath, or made a formal declaration, of allegiance to another State” or they have “given definite evidence of his determination to repudiate his allegiance to the Contracting State”.76 “Allegiance” to a State is 71 UNSC Res. 2322, 12 December 2016, preambular para. 12: “Underlining the importance of strengthening international cooperation … in order to prevent, investigate and prosecute terrorist acts, and recognizing the persisting challenges associated with strengthening international cooperation in combating terrorism including the stemming the flow of [foreign terrorist fighters] to and returning from conflict zones, in particular due to the cross border nature of the activity.” 72 UNGA Res. 2625 (XXV), 24 October 1970. 73 See e.g., Human Rights Council, Report of the United Nations High Commissioner for Human Rights on the protection of human rights and fundamental freedoms while countering terrorism, 19 December 2014, A/HRC/28/28, para. 44; and, for the UN Security Council’s definition of the term “foreign terrorist fighter”, UNSC Res. 2178, 24 September 2014, para. 6(a). 74 UN Counter-Terrorism Implementation Task Force, Guidance to States on human rights-compliant responses to the threat posed by foreign fighters, 2018, https://www.un.org/sc/ctc/wp-content/uploads/2018/08/HumanRights-Responses-to-Foreign-Fighters-web-final.pdf, para. 20. See also UN Economic and Social Council, Commission on Human Rights, Updated Set of principles for the protection of human rights through action to combat impunity, 8 February 2005, E/CN.4/2005/102/Add.1, p. 6: Impunity may be interpreted as being “the impossibility … of bringing the perpetrators of violations to account – whether in criminal, civil, administrative or disciplinary proceedings – since they are not subject to any inquiry that might lead to their being accused, arrested, tried and, if found guilty, sentenced to appropriate penalties, and to making reparations to their victims”; and Human Rights Council, Report of the United Nations High Commissioner for Human Rights on the protection of human rights and fundamental freedoms while countering terrorism, 19 December 2014, A/HRC/28/28, para. 44: “Accountability for all gross violations of international human rights law and violations of international humanitarian law through effective investigation and prosecution of those responsible is essential to ensure justice, to provide redress to victims and prevent further violations. The responsibility for accountability falls primarily on States, which are obliged to ensure investigations and, where the evidence warrants, prosecutions of such violations, meeting minimum international standards of justice.” 75 As of January 2020, three of the thirteen Contracting States which lodged declarations under Article 8(3) have limited their declarations to the grounds in Article 8(3)(a). These States may not therefore deprive individuals of nationality under Article 8(3)(b). The ten Contracting States whose declarations encompass Article 8(3)(b) may rely on that Article where the requirements therein, set out in paragraphs 69-71 of these Guidelines, are fulfilled. 76 This should be interpreted in line with the definition of a State in international law. See paragraph 60 above. UNHCR > GUIDELINES ON STATELESSNESS NO.5 21