statements of two presumed victims proposed by the representatives and one expert witness proposed by the State, as well as the final oral arguments of the parties and observations of the Commission on the preliminary objection and eventual merits, reparations and costs; in addition, he granted the parties and the Commission until April 2, 2012, to present their final written arguments and final written observations, respectively. 8. On March 30 and April 2, 2012, the State and the representatives, respectively, presented their final written arguments. The Commission presented its final written observations on the latter date. 9. On May 14, 2012, the Secretariat of the Court (hereinafter “the Secretariat”), on the instructions of the President, asked the representatives to provide as helpful evidence, by May 28, 2012, at the latest, documentation to prove the identity of each of the next of kin of Marco Bienvenido Palma Mendoza and their relationship to him, with regard to those persons the representatives considered to be presumed victims or beneficiaries. On May 24, 2012, the representatives presented the helpful evidence requested. On June 8, 2012, the Commission indicated that it had no observations to make on the said documentation. On June 12 that year, the State forwarded to the Court a brief with certain objections and considerations relating to the documentation submitted by the representatives (infra para. 25). 10. On June 12, 2012, the Secretariat of the Court, on the instructions of the President, asked the representatives and the State to forward the domestic norms regulating the mechanisms and effects of the discontinuance of criminal proceedings, as helpful evidence, by June 19, 2012 at the latest. The representatives and the State submitted the required documentation on June 18 and 19, 2012, respectively. On July 2 the same year, the representatives forwarded their observations. Neither the State nor the Commission submitted observations on the said documentation. III PRELIMINARY OBJECTION OF “FOURTH INSTANCE” 11. In its answering brief, the State filed the preliminary objection known as “court of appeal or fourth instance.” The Court will now analyze the admissibility of this objection. Arguments of the State and observations of the representatives and the Inter-American Commission 12. In its answering brief, the State asserted that: In relation to abduction and murder, the objection […] of the fourth instance has been proposed because those responsible for the crime were prosecuted; in other words, the domestic remedy was implemented. But, additionally, the State’s agencies responded to all requests for investigation regarding the alleged participation of State agents, reaching the conclusion that they were not involved, and no causal nexus of any kind was found. Regarding the filing of the application for habeas corpus, although this remedy was initially designed to resolve any anomalies in detentions carried out by State agents, in this case it constituted the basic reference point of the mechanisms to search for Mr. Palma. 13. At the public hearing held on March 1, 2012, as well as in its closing arguments, the State reiterated its arguments concerning the filing of the preliminary objection. It indicated that “the Commission’s actions had contributed to constituting” the fourth instance formula. The State argued that the Commission had exceeded the powers conferred by the American 5