contradictory versions surrounding the deprivation of life, 151 due diligence in the investigation must be evaluated in relation to the need to determine the veracity of the versions considered in the context of proceedings regarding what happened.152 Thus there were no face-to-face confrontations among witnesses with inconsistent or contradictory statements, even though such confrontations were requested by the Mr. Acosta's family. Worth underscoring is the erroneous application made by the National Criminal and Correctional Court of Appeals of the concept of "ne bis in idem", which it used to confirm the archiving of the case and its decision not to re-open the investigation. There was, nevertheless no one singled out, much less absolved, by a final judgment (which is where "ne bis in idem" applies), 108. In light of the above considerations, the Commission concludes that the Argentine State did not provide the family members of José Delfín Acosta Martínez with an appropriate and effective remedy, with which to clarify the legality of his detention and the reasons for his death. It is also to be noted that, despite receiving statements by Messrs. Ángel Acosta and Alberto Fresco in which they denounced threats and acts of intimidation, the State did not provide them with protective measures nor did it conduct any investigation thereof. It was the State's duty, in light of those complaints, to have duly investigated them and to have identified the sources of risk. In addition, proper inquiries into their denunciations and their correct incorporation into the investigation could have thrown light on responsibilities for the death of the victim and on what really happened while he was in State custody. 109. At the same time, the Inter-American Court has indicated on several occasions that the nextof-kin of victims of certain human rights violations may, in turn, become victims.153 Specifically, the Court found that the right to mental and moral integrity of the next of kin of victims [may be] violated based on the particular circumstances of the violations perpetrated against their loved ones and owing to the subsequent acts or omissions of the State authorities in relation to the facts.154 110. Consequently, the State is responsible for violation of the rights to judicial guarantees and judicial protection recognized in Articles 8.1 and 25.1 of the American Convention, as well as the right to mental and moral integrity established i Article 5.1 of the American Convention, all in conjunction with the obligations referred to in Article 1.1 of the same instrument, to the detriment of the family members of José Delfín Acosta Martínez. V. CONCLUSIONS 111. Based on its determinations of fact and law described above, the Inter-American Commission concludes that the Argentine State is responsible for violating the rights to life, humane treatment, and personal liberty, established in Articles 4.1, 5.1, 5.2, 7.1, 7.2, 7.3, 7.4, 7.5 and 24 of the American Convention, in conjunction with the obligations established in Article 1.1 and 2 of the same instrument, to the detriment of José Delfín Acosta Martínez. The Inter-American Commission likewise concludes that the Argentine State is responsible for violation of the rights to humane treatment, judicial guarantees, and judicial protection recognized in Articles 5.1, 8.1, and 25.1 of the American Convention taken in conjunction with Article 1.1 of that instrument, to the detriment of the family members of José Delfín Acosta Martínez identified in the relevant section of this report. VI. RECOMMENDATIONS 112. In light of the foregoing conclusions, I/A Court HR. Case of García Ibarra et al v. Ecuador. Preliminary Objections, Merits, Reparations, and Costs. Judgment of November 17, 2015. Series C No. 306, par. 143. 152 I/A Court HR. Case of García Ibarra et al v. Ecuador. Preliminary Objections, Merits, Reparations, and Costs. Judgment of November 17, 2015. Series C No. 306, par. 139. 153 I/A Court H.R., Case of Cantoral-Huamaní and García-Santa Cruz v. Peru. Preliminary Objection, Merits, Reparations and Costs. Judgment of July 10, 2007. Series C No. 167, par. 112; I/A Court H.R., Case of Bueno-Alves v. Argentina. Judgment of May 11, 2007. Series C. No. 164 par. 102. 154 I/A Court H.R., Case of Cantoral-Huamaní and García-Santa Cruz v. Peru. Preliminary Objection, Merits, Reparations and Costs. Judgment of July 10, 2007. Series C No. 167, par. 112; I/A Court H.R., Case of Vargas-Areco. Judgment of September 26, 2006. Series C No. 155, paras 103 and 96. 151