III. THEMATIC SUMMARY OF SOME CENTRAL ISSUES PERTAINING TO THE CONVENTION 1. UNIVERSAL JURISDICTION 2. IMMUNITY TO HEADS OF STATES AND DIPLOMATS? To be in a position to bring criminal proceedings against the offender, torture must firstly be a crime in the domestic law of the State concerned. This issue is addressed in Article 4 of the Convention, which obliges States Parties to ensure that all acts of torture are offences under their criminal law. Secondly, the State must have jurisdiction over the offence. This is ensured in Article 5, which provides that States Parties shall establish their jurisdiction, including universal jurisdiction, for the offence of torture. In other words, a State Party shall take any necessary measures to establish its jurisdiction over the crime of torture, not only in cases where the crime of torture is linked to the State by territoriality (the torture was committed on the territory of the State) or nationality (the offender is a national of the State), but also in cases where the only link to the State concerned is the presence of the alleged offender on territory under the effective control of the State. The States Parties are only allowed discretion concerning the question of the establishment of universal jurisdiction in cases where the victim of torture is their own national. 64 Having ensured that torture is a crime in national law and that the States Parties have established jurisdiction, including universal jurisdiction, over the crime, Article 7 obliges States Parties to exercise such jurisdiction. The main provision regarding the exercise of (universal) jurisdiction is Article 7 §1. It provides that States Parties are obliged to either hand over suspected torturers in their territories to the prosecuting authorities for the purpose of prosecution, unless the suspected torturers are to be extradited to another State with jurisdiction which intends to prosecute them. This is also called the principle of aut dedere aut judicare, meaning “either extradite or prosecute”. One important question is whether States Parties to the Convention may exercise universal jurisdiction over nationals from non-States Parties. However, there now appears to be a significant body of practice indicating that such jurisdiction is permissible under international law.226 2. IMMUNITY TO HEADS OF STATES AND DIPLOMATS? Article 5 §2 of the Convention imposes an obligation on States to establish jurisdiction over all crimes of torture, irrespective of the status of the alleged offenders. The rationale of the Convention is, after all, that suspects of torture must not be able to find a safe haven, and that any suspect of torture must fear prosecution always and everywhere.227 The CAT has expressed the view that the States’ obligations to bring alleged torturers to justice extends to the highest officials. In direct reference to the case involving the former President of Chile, Pinochet Ugarte, whom the United Kingdom had been requested to extradite to Spain on charges of, inter alia, complicity in the torture of Spanish citizens, the CAT expressed the view that Article 5 §2 of the Convention