HASSAN v. THE UNITED KINGDOM JUDGMENT – SEPARATE OPINION 61 Article 31 of the Vienna Convention on the Law of Treaties of 23 May 1969, from which the Court concludes as follows: Firstly, State practice indicates that States do not derogate from their obligations under Article 5 in order to detain persons on the basis of the Third and Fourth Geneva Conventions during international armed conflicts (see paragraph 101 of the judgment). Secondly, the Convention must be interpreted in harmony with other rules of international law of which it forms part. The provisions in the Third and Fourth Geneva Conventions relating to internment, at issue in the present case, were designed to protect captured combatants and civilians who pose a security threat. Thus, the lack of formal derogation under Article 15 does not prevent the Court from taking account of the context and the provisions of international humanitarian law (see paragraphs 102-103). Thirdly, even in situations of international armed conflict, the safeguards of the Convention continue to apply, albeit interpreted against the background of the provisions of international humanitarian law. By reason of the co-existence of the safeguards provided by international humanitarian law, the grounds of permitted deprivation of liberty under Article 5 § 1 should be “accommodated, as far as possible”, with the taking of prisoners of war and the detention of civilians who pose a risk to security under the Third and Fourth Geneva Conventions (see paragraph 104). I shall discuss each argument in turn. IV. 11. The rationale relating to State practice is flawed for three reasons. 12. Firstly, the State practice in question is based on a fundamental premise, invoked by the Government in this case (see paragraph 86), which relates to the scope of the Convention’s extra-territorial reach. The premise is the following: Article 5 does not apply to situations of international armed conflict for the simple reason that Article 1 jurisdiction under the Convention is not extra-territorial in the sense of being applicable in such conflict situations. In Al-Skeini v. the United Kingdom [GC], 55721/07, § 137, 7 July 2011, the Court confirmed, in clear and unequivocal terms, its prior rulings in the cases of Öcalan v. Turkey [GC] (no. 46221/99, 12 May 2005), Issa and Others v. Turkey (no. 31821/96, 16 November 2004), Al-Saadoon and Mufdhi v. the United Kingdom ((dec.), no. 61498/08, 30 June 2009), and Medvedyev and Others v. France [GC] (no. 3394/03, 23 March 2010), to the effect that Member States’ obligations under the Convention remain in place “whenever” the State, through its agents, “exercises control and authority over an individual” on the territory of another State. The Court made no distinction between situations arising in peacetime or in internal or international conflict. Further, the Court explicitly stated (see Al-Skeini, cited