experts have specified that, “(…) the general IHL rule is that internment must cease [at the latest] at the end or close of active hostilities in the armed conflict in relation to which a person was interned. The close of hostilities is a factual matter that is determined on a case by-case basis.”147 144. During an international armed conflict, international humanitarian law provides for substantive and procedural rules that “limit the ability to derogate” from international human rights law and “mitigate the risk of arbitrary detention”.148 Article 4 of the ICCPR allows for derogations during armed conflict, including from some provisions of Article 9, only to the extent where the “life of the nation” is threatened. These measures are to be temporary and strictly required and may not be justified where the result “could be achieved through less intrusive means”. The measures must also be consistent with other international laws, including international humanitarian law.149 A State party derogating from ICCPR provisions must notify other State parties through the UN SecretaryGeneral.150 The United States has never given any notification of an official derogation from the ICCPR.151 b. Domestic Standards 145. The US Constitution prohibits arbitrary detention and provides detainees with the ability to challenge the lawfulness of their arrest or detention before a court. The Fifth Amendment stipulates that no one is to be deprived of their liberty without due process of law.152 The Fourth Amendment recognizes the right to be free from unreasonable searches and seizures.153 The right to be informed of the nature and reasons for accusations and to have assistance of counsel in all criminal prosecutions is protected under the Sixth Amendment.154 Article 1 Section 9 of the US Constitution, also known as the Suspension Clause, grants the privilege of the writ of habeas corpus, which allows detainees to challenge the lawfulness of their detention. The writ can only be suspended where “in Cases of Rebellion or Invasion the public Safety may require it”.155 The privilege of habeas corpus, as discussed below, is now available to Guantánamo detainees.156 The 147 Pejic, “The protective scope of Common Article 3”, op. cit., note 145, p. 23. UN HRC, General Comment No. 35, op. cit., note 92, para. 66; UN HRC, General Comment No. 29, op. cit., note 111, paras. 3, 9. 149 ICCPR, Art. 4; UN HRC, General Comment No. 29, ibid., para. 4; UN Special Procedures, “Situation of detainees at Guantánamo Bay”, op. cit., note 23, paras. 12-13. 150 ICCPR, Art. 4(3). 151 UN Special Procedures, “Situation of detainees at Guantánamo Bay”, op. cit., note 23, para. 13. 152 The Fourteenth Amendment also prohibits the deprivation of liberty without due process, but it relates to state action, which is not addressed in this report. US Constitution, 17 September 1787, Fifth Amendment, <http://www.law.cornell.edu/constitution/overview>: “nor be deprived of life, liberty, or property, without due process of law”. 153 “The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated.” US Constitution, Fourth Amendment. 154 “In all criminal prosecutions, the accused shall enjoy the right to (…) to be informed of the nature and cause of the accusation (…) and to have the Assistance of Counsel for his defence.” US Constitution, Sixth Amendment. 155 US Constitution, Art. 1 § 9. 156 United States Supreme Court, Boumediene v. Bush, op. cit., note 73; United States Supreme Court, Rasul v. Bush, op. cit., note 72. The latter case dealt with a federal statute rather than a constitutional right. 148 58