-32003), I also insisted in the need for "acknowledgement of the effects of the American Convention vis-à-vis third parties (Drittwirkung),"6 and added that "In order to be effective, the protection of human rights determined by the American Convention encompasses not only the relations between individuals and the public authorities, but also their relations with third parties (clandestine or paramilitary groups or other groups of individuals). This reveals the new dimensions of international human rights protection, and also the vast potential of the existing protection mechanisms such as the American Convention - used to protect collectively the members of a whole community, even though the grounds for the proceedings may be the harm - or the probability or imminence of harm - of individual rights" (para. 4). 8. It is worth recalling that, in its transcendent Advisory Opinion No. 18 on The Juridical Status and Rights of Undocumented Migrants (of September 17, 2003), the Inter-American Court correctly maintained that the rights protected by the American Convention must be respected in both relations between individuals and State authorities, and in inter-individual relations, and the obligation to guarantee may also be required of the States Parties in that regard (para. 140) under Article 1(1) of the Convention. Thus, the Convention provisions of protection have effects in relation to third parties (individuals), thereby establishing the nature erga omnes of the protection obligations (Drittwirkung). In my concurring opinion to that Advisory Opinion N.18, I recalled that these obligations erga omnes, characterized by jus cogens (from which they derive)7 are endowed with a necessarily objective nature and therefore encompass all the beneficiaries of the juridical norms (omnes), both the members of the State's bodies and individuals (para. 76). And I continued: "In my view, we can consider such obligations erga omnes from two dimensions, one horizontal and the other vertical, which complement each other. Thus, the obligations erga omnes of protection, in a horizontal dimension, are obligations pertaining to the protection of the human beings due to the international community as a whole8. In the framework of conventional international law, they bind all the States Parties to human rights treaties (obligations erga omnes partes), and, in the ambit of general international law, they bind all the States which compose the organized international community, whether or not they are Parties to those treaties (obligations erga omnes lato sensu). In a vertical dimension, the obligations erga omnes of protection bind both the organs and agents of (State) public power, and the individuals themselves (in the inter-individual relations). For the conformation of this vertical dimension have decisively contributed the advent and the evolution of the International Law of Human Rights. But it is surprising that, until now, these horizontal and vertical dimensions of the obligations erga omnes of protection have passed entirely unnoticed from contemporary legal doctrine. Nevertheless, I see them clearly shaped in the legal regime itself of the American Convention on Human Rights. Thus, for example, as to the vertical dimension, the general obligation, set forth in Article 1(1) of the American Convention, to respect and to ensure respect for the free exercise of the rights protected by it, generates effects erga 6 . Cf. paras. 2-3 of the said opinion. . In the same opinion, I clarified that "By definition, all the norms of jus cogens necessarily generate obligations erga omnes. While jus cogens is a concept of material law, the obligations erga omnes refer to the structure of their performance on the part of all the entities and all the individuals bound by them. In their turn, not all the obligations erga omnes necessarily refer to norms of jus cogens" (para. 80). 8. IACourtHR Case of Blake versus Guatemala (merits), Judgment January 24, 1998. Separate Opinión of Judge A.A. Cançado Trindade, para. 26, and cf. para. 27-30. 9. Cf. In this regard, in general, the resolution adopted by the Institute of Internacional LAw (IIL) at the 1989 session in Santiago de Compostela (Article 1), in: IDI, 63 Annuarie de l’Institut de Droit International (1989)-II, pp. 286 and 288-289 7