33. The Commission is competent ratione loci to take cognizance of the petition in that it sets forth violations of rights protected by the American Convention that allegedly took place and continue to take place in the territory of a State Party. The IACHR is also competent rationetemporis because the obligation to respect and guarantee the rights protected by the American Convention was already in effect for the State as of the date the actions referred to in the petition allegedly occurred and also because violations of inmates’ human rights at the Penitentiary of Mendoza and its offices continue to occur. Finally, the Commission is competentrationemateriae because the petition claims violations of human rights protected by the American Convention. B. Other admissibility requirements for the petition 1. Exhaustion of domestic remedies 34. Article 46(1)(a) of the Convention provides that the admissibility of a petition submitted to the Commission is subject to the requirement that remedies under domestic jurisdiction must have been filed and exhausted, in accordance with generally recognized principles of international law. The preamble to the Convention states that it grants international protection to support or complement the protection provided by a State’s domestic laws. 2 The rule of prior exhaustion of domestic remedies allows the State to resolve the problem according to its internal law before facing an international proceeding, which is particularly valid in the international jurisdiction of human rights. 35. In this case, the petitioners show that they have filed a series of habeas corpus actions for unjustified aggravation of their conditions of detention. Those actions have been declared admissible in various courts of Mendoza that have established, on several occasions, a series of measures to be complied with by the Government. 36. For its part, the State has not alleged a failure to exhaust domestic remedies. As the InterAmerican Court of Human Rights clearly indicated, a State that seeks to invoke a failure to exhaust domestic remedies must do so expressly in the first stage of the proceeding. 3 In the instant case, the State did not expressly invoke the failure to exhaust domestic remedies; it simply acknowledged receipt of the petition and deemed it advisable not to express its views in this regard. Against this backdrop, the tacit waiver of an objection based on failure to exhaust domestic remedies can be presumed.4 37. Although it can be inferred from the State’s communication that it reserves the right to address [the issue] on another occasion, it must be noted in this regard that the InterAmerican Court has indicated that, in order to be timely, an objection based on failure to exhaust domestic remedies must be filed in the initial stages of a proceeding, in the absence of which the tacit waiver of the use of that objection by the interested State can be presumed. 5 For the foregoing reasons, the Commission concludes that a tacit waiver has been given by the State and that this requirement has been met. 2. Timeliness of the petition 38. In accordance with the provisions of Article 46(1)(b) of the Convention, in order to be admissible, a petition must be lodged within six months of the date when the complaining party has been notified of a final decision handed down at the national level. The six months 2 See second paragraph in fine of the Preamble to the American Convention. 3 See Inter-American Court of Human Rights, The AwasTigni (Sumo) Mayagna Community Case, Preliminary Objections, Judgment of February 1, 2000, para. 55 and the following. 4 Inter-American Court of Human Rights, Velásquez Rodríguez Case. Preliminary Objections. Judgment of June 26, 1987, para. 88. See also IACHR, Report N° 39/96, Case 10.897, Guatemala, October 16, 1996, para. 35, and Report N° 53/96, Case 8074, Guatemala, December 6, 1996. 1996 IACHR Annual Report. See also Report N° 25/94, Case 10.508, Guatemala, September 22, 1994, p. 52. 1994 IACHR Annual Report. 5 Inter-American Court of Human Rights, Velásquez Rodríguez Case. Preliminary Objections. Judgment of June 26,1997, para. 8; FairénGarbi and Solís Corrales Case.Preliminary Objections. Judgment of June 26, 1987, para. 87;GangaramPanday Case. Preliminary Objections.Judgment of December 4, 1991, para.38; Loayza Tamayo Case.Preliminary Objections.Judgment of January 31, 1996, para. 40. 6