16 force in all circumstances, including during states of exception. This Court has previously established as indispensable guarantees those judicial proceedings that are normally essential to guarantee the full exercise of the rights and freedoms33, which will vary according to the affected rights34. The said guarantees are those to which the Convention expressly refers in Articles 7(6) and 25(1), considered within the framework and the principles of Article 8, and also those necessary to the preservation of the rule of law, even during the exceptional legality that results from the suspension of guarantees35. The said indispensable judicial guarantees must be preserved in order to verify the necessity, reasonability and proportionality of the specific measures adopted in exercise of those exceptional powers36. 55. On the other hand, regarding the general duty embodied in Article 2 of the Convention, the Court has repeatedly held that: [u]nder the law of nations, a customary law prescribes that a State that has signed an international agreement must introduce into its domestic laws whatever changes are needed to ensure execution of the obligations it has undertaken. This principle is universally valid and has been characterized in case law as an evident principle (“principe allant de soi”; Exchange of the Greek and Turkish populations, advisory opinion, 1925, C.P.J.I., series B, no. 10, p. 20)37. 56. This principle is enshrined in Article 2 of the Convention, which sets forth the general duty of each State Party to adjust its domestic law to the provisions of the Convention to guarantee the rights enshrined therein38, which implies that the domestic legal measures must be effective (effet utile principle)39. 57. Certainly, Article 2 of the Convention fails to define which measures are appropriate to adjust the domestic law to the Convention; obviously, this is so because it depends on the nature of the rule requiring adjustments and on the circumstances of each specific situation. Therefore, the Court has interpreted that such adjustment implies adopting two sets of measures, knowingly: (i) repealing rules and practices of any nature entailing violations of the guarantees provided for in the Convention or disregarding the rights enshrined therein or impeding the exercise of such rights, and (ii) adopting rules and developing practices aimed at effectively ensuring the said guarantees40. The Court has taken the view that the first set of duties is breached while the rule or Cf. similarly, Habeas corpus in Emergency Situations (Arts. 27(2), 25(1) and 7(6) American Convention on Human Rights), supra note 25, para. 29. 33 Cf. similarly, Habeas corpus in Emergency Situations (Arts. 27(2), 25(1) and 7(6) American Convention on Human Rights), supra note 25, para. 28. 34 Cf. similarly, Judicial Guarantees in States of Emergency (Arts. 27(2), 25 and (8) American Convention on Human Rights). Advisory Opinion OC-9/87 of October 6, 1987. Series A No. 9, para. 38. See also Case of Durand and Ugarte. Judgment of August 16, 2000. Series C No. 68, para. 107. 35 Cf. Judicial Guarantees in States of Emergency (Arts. 27(2), 25 and (8) American Convention on Human Rights), supra note 35, para. 21. See also Case of Durand and Ugarte, supra note 35, para. 99. 36 Cf. Case of Garrido and Baigorria.Reparations. Judgment of August 27, 1998. Series C No. 26, para. 68. See also Case of La Cantuta, supra note 7, para. 170, and Case of Almonacid Arellano et al., supra note 14, para. 117. 37 38 Cf. Case of “The Last Temptation of Christ” (Olmedo-Bustos et al.). Judgment of February 5, 2001. Series C No. 73, para. 87. See also Case of La Cantuta, supra note 7, para. 171, and Case of Almonacid Arellano et al., supra note 14, para. 117. 39 Cf. Case of Ivcher-Bronstein. Competence. Judgment of September 24, 1999, para. 37; Case of “The Last Temptation of Christ” (Olmedo-Bustos et al.), supra note 38, para. 87. See also Case of La Cantuta, supra note 7, para. 171, and Case of the "Juvenile Reeducation Institute". Judgment of September 2, 2004. Series C No. 112, para. 205. 40 Cf. Case of Castillo-Petruzzi et al. Judgment of May 30, 1999. Series C No. 52, para. 207. See also Case of La Cantuta, supra note 7, para. 172, and Case of Almonacid Arrellano et al., supra note 14, para. 118.