applied or tolerated by the state, because the imperative need to prevent the repetition of said events depends, to a large extent, on preventing them from going unpunished and on meeting the expectations of both the victims and society as a whole of gaining access to knowledge of the truth of what happened. The elimination of impunity by all legal means available is a basic element for the elimination of extrajudicial killings, torture, and other grave human rights violations.161 151. According to inter-American case law, it turns out that, when there is a report on the disappearance of a person, there is an integral linkage between the state’s response and the protection of the life and integrity of the person who is reported missing. The Commission reiterates that, when there are reasonable reasons for suspecting that a person has been subjected to disappearance, it is indispensable for prosecution and judicial authorities to act quickly and immediately by ordering timely and necessary measures aimed at ascertaining the whereabouts of the victim or the place where he or she might be found deprived of liberty.162 152. In the words of the Inter-American Court, so that an investigation of an alleged forced disappearance can be conducted effectively and with due diligence:163 the authorities in charge of the investigation must use all necessary means to take those measures and make those inquiries that are essential and opportune to clarify the fate of the victims. On numerous occasions, this Court has ruled on the obligation of States to conduct a genuine search, using the appropriate administrative or judicial mechanism, during which every effort is made, systematically and rigorously, with the adequate and appropriate human, technical and scientific resources, to establish the whereabouts of the persons disappeared. The return of the body of a disappeared person is extremely important for their next of kin, because it allows them to bury him or her in keeping with their beliefs, and also to close the mourning process that they have been experiencing throughout these years. In addition, the remains are evidence of what happened and, together with the place where they are found, can provide valuable information on the perpetrators of the violations or the institution to which they belong. 153. Likewise, in the case of forced disappearances, the codification of the crime of forced disappearance must have priority in the investigations that need to be launched or continued at the domestic level. Because it involves a crime that is prolonged in time, when the codification of the crime of forced disappearance of persons comes into force, the new law applies, although this does not means it can be applied retroactively.164 154. Furthermore, pursuant to Article 1.1 of the American Convention, the obligation of guaranteeing the rights recognized in Articles 5.1 and 5.2 of the American Convention entails the state’s duty to investigate possible acts of torture or other cruel, inhuman, or degrading treatment. This obligation to investigate is reinforced by the provisions of Articles 1, 6, and 8 of the Inter-American Convention to Prevent and Punish Torture which requires the state to “take effective measures to prevent and punish torture in the sphere of its jurisdiction,” as well as to “prevent and punish […] other cruel, inhuman, or degrading treatment.”165 155. According to inter-American case law, it is clear that, by virtue of Articles 8 and 25 of the Convention, when the authorities are apprised of a possible case of forced disappearance or torture, they have the reinforced duty of promoting and conducting the investigation, which includes the following relevant matters for the instant case: (i) to start ex officio the investigation as long as there is a complaint or well-founded reason for suspecting that said crimes have been committed; (ii) to order and bring forward the relevant evidence in line with the duty of due diligence; (iii) to guarantee independence and impartiality in the investigation; and (iv) to remove the obstacles that jeopardize the adequate development of the investigation, among others. I/A Court H.R. Case of the Massacres of El Mozote and nearby places v. El Salvador. Merits, Reparations, and Costs. Judgment of October 25, 2012. Series C No. 252, para. 244. 162 I/A Court H.R. Case of Ibsen Cárdenas e Ibsen Peña v. Bolivia. Merits, Reparations, and Costs. Judgment of September 1, 2010. Series C No. 217, para. 167. 163 I/A Court H.R. Case of Rodríguez Vera et al. (the Disappeared from the Palace of Justice) v. Colombia. Preliminary Objections, Merits, Reparations, and Costs. Judgment of November 14, 2014. Series C No. 287, para. 480. 164 I/A Court H.R. Case of Gelman v. Uruguay. Merits and Reparations. Judgment of February 24, 2011. Series C No. 221, para. 236. 165 IACHR. Report on the Merits No. 74/15. Mariana Selvas Gomez et al. Mexico. October 28, 2015, para. 378; I/A Court H.R. Case of J. v. Peru. Preliminary Objection, Merits, Reparations, and Costs. Judgment of November 27, 2013. Series C No. 275, para. 341. 161