2 had in mind the concomitant imperatives and needs of realization of justice, and of preservation of the juridico-procedural equality and security under the American Convention. 6. As to the distinct role of the individual petitioners and of the Inter-American Commission in the procedure before the Court, this latter took into consideration the approaches of both the thesis of procedural law, with emphasis on the exclusive faculty of the States Parties and of the Commission to submit a case to the Court (Article 61(1) of the American Convention), and the thesis of substantive law, with emphasis on the condition of the individuals of titulaires of the rights set forth in the Convention. From the ineluctable tension between the two thesis (which correspond to two trends of juridical thinking), there resulted the understanding that the new faculty of the petitioners to present in an autonomous way their arguments before the Court should pertain to the factual and juridical elements contained in the complaint presented by the Commission3. 7. In the one year and a half of the new Regulations of the Court being in force, the petitioners have reiteratedly referred to rights, other that the ones contained in the complaint presented by the Commission, which they considered to have also been violated, not only in the present case of the Five Pensioners versus Peru, but also on other recent occasions4, in contentious cases which in due course will be resolved by the Court in the respective Judgments. In the present case, the controversy arisen between the representatives of the alleged victims and their relatives, on theone hand, and the Inter-American Commission, on the other (pars. 149-150), has required from the Court a pronouncement on this specific point. 8. The Commission opposed itself that the representatives of the alleged victims and their relatives could add, - in their brief of submissions, arguments and evidences, new factual and juridical elements (additional rights) besides the ones already contained in the complaint interposed by the Commission before the Court. This controversy, in a way, leads the Court, in the present Judgment in the case of the Five Pensioners versus Peru, to clarify, and to place in adequate perspective, the fundamentally distinct roles of the petitioners and of the Commission in the procedure before the Tribunal. 9. The Court, called upon to pronounce itself on this matter, has had in mind the experience - of one and a half years so far - which begins to accumulate on the subject at issue, under its new Regulations, as well as, - once more, as always, - the concomitant imperatives of realization of justice, and of preservation of the juridicoprocedural equality and security in the procedure under the Convention. As to the factual elements of the complaint presented by the Commission (the object of the process), the Court has accepted the argument of the Commission, - with the exception, naturally, of the supervening facts, - in the following terms (pars. 153-154): "As to the facts object of the process, this Tribunal considers that it is not admissible to allege new facts, distinct from those raised in the complaint, without prejudice of referring to those which may explain, clarify or discard the onew that have been mentioned in the complaint, of rather, respond to the submissions of the complainant. 3 . 4 . Cf. Informe..., op. cit. infra n. (7), pp. 28-30. Cases Mirna Mack Chang versus Guatemala, Maritza Urrutia versus Guatemala, Centro de Reeducación del Menor versus Paraguay, Ricardo Canese versus Paraguay, Juan Sánchez versus Honduras, and Gómez Paquiyauri versus Peru.