prohibiting torture, the extradition of alleged torturers to face prosecution for their alleged offences is a crucial element of the regime envisaged by the CAT. Co-operation between states, including the establishment of extradition and deportation guarantees, is therefore vital to containing international crime, including terrorism. The principle of non-refoulement The absolute nature of protection from torture or inhuman or degrading treatment means that it would violate the right to protection from torture, inhuman or degrading treatment to deport (refouler), render or extradite an individual in the knowledge that they will be tortured or subject to inhuman or degrading treatment. The principle of non-refoulement prohibits the expulsion of persons to states where there are substantial grounds for believing they would be at risk of torture or other serious human rights violations.393 The absolute character of the principal of non-refoulement in international human rights law394 has been emphasized at the UN level in a joint statement that stressed that “no one shall be deported to a State where he or she would be in danger of being subjected to torture.”395 This reflects a growing body of case law relating to the absolute prohibition on refoulement where there is a danger of torture, inhuman or degrading treatment or punishment. Also directly connected to this principle is the prohibition of the collective expulsion of aliens. Article 4 of Protocol 4, ECHR states categorically and in absolute terms, the “[c]ollective expulsion of aliens is prohibited.” Standard of proof required In order for the principle of non-refoulement to be engaged, the risk of such treatment has to be “personal and present”. A mere suspicion of possible torture is insufficient to engage this protection, but the test need not meet the standard of being highly probable.396 To rely upon the protection from torture provisions, applicants must show that their expulsion would have the foreseeable consequence of exposing them to a “real and personal” risk of being tortured. As protection from torture is absolute, considerations of a procedural nature or the nature of the activities in which the person engaged are not relevant. The protection exists “irrespective of whether the individual concerned has committed crimes and the seriousness of those crimes.”397 393 This principle is also contained in Article 33 of the Convention relating to the status of Refugees of 1951 and in common Article 3 of the Geneva Conventions and the additional protocols thereto. 394 As opposed to in International Refugee Law (Article 33(2) of Geneva 1951 Convention) which permits limitations in case of “a refugee whom there are reasonable grounds for regarding as a danger to the security of the country in which he is, or who, having been convicted by a final judgement of a particularly serious crime, constitutes a danger to the community of that country.” 395 Joint statement of the UN Committee against Torture, the Special Rapporteur of the Commission on Human Rights on the Question of Torture, the Board of Trustees of the United Nations Voluntary Fund for Victims of Torture and the United Nations Deputy High Commissioner for Human Rights and Officer in charge of the Office of the High Commissioner for Human Rights in the occasion of the United Nations International Day in Support of Victims of Torture, 26 June 2003. 396 CAT, General Comment No. 01 (Implementation of article 3 of the Convention in the context of article 22), doc. A/53/44, annex IX, 21 November 1997, para. 7. 397 Op. cit., note 347, UN OHCHR, Combating Torture, p. 35. 138 Countering Terrorism, Protecting Human Rights