22 Arguments of the representatives of the victims 52. With regard to the arguments of the State concerning reparations, the representatives of the victims indicated that: a) As a result of the recent regulatory reforms, “procedural economy has been privileged” in cases before the Court, since Article 36(6) of the Rules of Procedure of the Court, which entered into force on June 1, 2001, authorizes the Court to decide on the preliminary objections and the merits of the case in a single judgment, while Article 56(1) of the Rules of Procedure establishes a separate procedure for deciding reparations only “when no specific ruling on reparations has been made in the judgment on the merits”; b) Although it is true that the Court had the practice of delivering three judgments in each case (preliminary objections, merits and reparations), as it did in the Velásquez Rodríguez case, “this practice has changed owing to the new Rules of Procedure”; c) “The determination of compensation, and also its amount, is adapted to the criteria established by the case law of the Court and the principles of international law generally recognized in this matter”; d) Regarding “the violation of legal writings on succession,” according to Article 27 of the 1969 Vienna Convention on the Law of Treaties, a State may not invoke the provisions of internal law as justification for its failure to perform a treaty; e) Likewise, Article 68(1) of the American Convention establishes that the States undertake to comply with the judgment of the Court in any case to which they are parties; f) “The State has made no distinction between the victim’s heirs and [...] the next of kin who are directly affected by a violation that makes them eligible for reparation, a situation that is determined clearly in sections XIII to XV of the judgment”; g) The representatives had indicated clearly the family or affective relationship that linked each person to the victim in its written and oral arguments, “and they were not contested by the State,” so that the State cannot request a review of this point once judgment has been delivered; h) The determination of the beneficiaries and of the amount corresponding to each of them for compensation established in the judgment coincides with the elements established by the Court in its case law. Specifically, the representatives considered that in the judgment on reparations in the Villagrán Morales et al. case, the Court had indicated “that the next of kin of a deceased person must be considered beneficiaries of reparations as successors and, also, as victims of a violation” and that the damage caused to other next of kin