Introduction 7 degrading treatment or punishment throughout the world’.38 This goal was achieved by three different types of measures: repression against individual perpetrators of torture by means of domestic criminal law and the principle of universal jurisdiction; recognition of the right of victims of torture to a remedy and adequate reparation; and comprehensive obligations of States parties to prevent torture and cruel, inhuman or degrading treatment or punishment. Although the term ‘cruel, inhuman or degrading treatment or punishment’ has not been defined and the different categories of ill-​treatment not delineated,39 Article 1 CAT is the first provision in international law which provides for a legal definition of torture which, nevertheless, is subject to controversial discussions in legal theory and practice.40 Since most of the Convention’s provisions, above all those related to the criminal responsibility of the perpetrators, only apply to torture and not to cruel, inhuman or degrading treatment or punishment, the legal distinction between torture and other forms of ill-​treatment is significant. Most preventive obligations of States parties equally apply to torture and cruel, inhuman or degrading treatment or punishment.41 In addition to the general obligation of States parties under Articles 2 and 16 to take effective legislative, administrative, judicial, or other measures to prevent torture and cruel, inhuman or degrading treatment or punishment in any territory under their jurisdiction, States also have specific obligations to include the prohibition of torture and cruel, inhuman or degrading treatment or punishment in the training curricula of law enforcement and prison personnel (Article 10), to keep interrogation rules and methods under systematic review (Article 11), and to carry out prompt and impartial ex officio investigations, wherever there is reasonable ground to believe that an act of torture or cruel, inhuman or degrading treatment or punishment has been committed (Article 12). Since victims of torture are often too afraid or unable to lodge a complaint against their tormenters, this obligation of police chiefs, prison directors, public prosecutors, police and prison doctors, and others to start ex officio a thorough investigation before an independent body whenever they suspect that an act of torture or cruel, inhuman or degrading treatment or punishment might have occurred, is of utmost importance for the prevention of torture. In addition, no confession or information extracted by torture shall be admitted as evidence in any judicial or administrative proceedings (Article 15). If the relevant authorities were to take the inadmissibility of torture tainted evidence seriously, a major incentive for extracting information and confessions through torture would disappear. Finally, States parties to the OP have an additional preventive obligation to establish one or several independent national preventive mechanisms with the power to carry out unannounced visits to all places of detention, to conduct private interviews with all detainees, and to make recommendations to the relevant authorities with the aim of preventing torture and improving conditions of detention (Articles 17–​23 OP). Another important provision for the prevention of torture is the principle of non-​ refoulement in Article 3 CAT. States are not only under an obligation to refrain from practising torture and cruel, inhuman or degrading treatment or punishment by their own officials on their own territory, but they are also required to refrain from expelling, returning, or extraditing a person to another State where there are substantial grounds 39 40   See below Preamble.   See below Art 16.   See below Art 1, 3.1.   See below Art 16, which contains an explicit reference to the obligations contained in Arts 10, 11, 12, and 13, in particular. 38 41