A/HRC/4/25 page 15 46. The principle of non-discrimination during states of emergency may be inferred both from article 4, paragraph 1, of the International Covenant on Civil and Political Rights and, in general, from the principle of non-discrimination underpinning international human rights law. In this connection, provisions which differentiate between nationals and foreigners in terms of enjoyment of their rights, including jurisdictional rights, may contravene the principle of non-discrimination. An example of this can be seen in the United Kingdom’s Anti-Terrorism, Crime and Security Act 2001. This Act empowered the Home Office to detain indefinitely and without trial foreigners suspected of participating in terrorist activities who could not be deported. In response to the allegation that the powers contained in the Act violated the right to individual liberty, the right to a fair trial, the right to non-discrimination and other rights, the Government argued that it was confronted with an emergency. Three years later, the House of Lords Judicial Committee found that it was not acceptable for laws to differentiate between foreigners and nationals,10 which is reflected in the Terrorism Act 2006. 47. Lastly, the principle of the compatibility, consistency and complementarity of the various provisions of international law prohibits the application of emergency measures which, although admissible under a given international treaty, conflict with other international obligations, whether they come under customary or treaty law. The right to a fair trial - enshrined in articles 14 and 9 of the Covenant - must be further analysed in the light of peremptory norms and on the basis of obligations arising from other provisions of international law, in particular international humanitarian law. 48. There are peremptory norms which require that general safeguards concerning detention must be upheld even during a state of emergency. Many international precedents have identified many other non-derogable rights, such as the right to be informed of the reasons for arrest,11 providing safeguards against incommunicado or indefinite detention, the right to file a petition for habeas corpus, safeguards against abuses during questioning,12and maintaining normal standards of proof. Also inherent in non-derogable rights are procedural measures intended to ensure their protection, as a result of which the provisions relating to those measures may not be derogated from. In this connection, the reaction of the Supreme Court of the United States is to be welcomed. In the Rasul v. Bush case the Court found that the petitioners had the right to file a habeas corpus petition before any federal court,13 thereby 10 See note 7 above. 11 With emergency laws in force in Northern Ireland, the practice of not informing persons arrested of the reasons for their arrest was declared illegal by the courts of the United Kingdom. EHCR also refers to the practice in Ireland v. the United Kingdom, p. 76, para. 198. 12 Not only are such abuses prohibited, the evidence is considered invalid. See in this connection the Human Rights Committee’s general comment No. 13 (CCPR/C/21/Add.3), p. 6. 13 Regrettably, the Military Commissions Act, adopted in September 2006, among other regressive provisions, also ignores this fact.