62 321. The IACHR continued to monitor the situation closely, and on March 26, 1993, it sent a message to the Salvadoran Government before the deadline that the President had for vetoing the recently approved law, stating that: The Legislative Assembly’s passage of a General Amnesty Law on March 20, immediately after publication of the Report of the Truth Commission, could compromise effective implementation of the Truth Commission’s recommendations and eventually lead to a failure to comply with the international obligations undertaken by the Government of El Salvador when it signed the Peace Agreements. The Commission would like to call Your Excellency’s attention to the fact that the political agreements concluded among the parties in no way relieve the State of the obligations and responsibilities it has undertaken by virtue of its ratification of the American Convention on Human Rights and other international instruments on the same subject. Under Article 27 of the Vienna Convention on the Law of Treaties, a State cannot unilaterally invoke provisions of its domestic law as justification for its failure to perform the legal obligations imposed by an international treaty. Finally, Article 144 paragraph 2 of the Constitution of El Salvador states that “the law shall not modify or derogate that agreed upon in a treaty in effect in El Salvador. In the event of a conflict between the treaty and the law, the treaty will prevail.” The Inter-American Commission on Human Rights would also like to remind Your Excellency’s Government that El Salvador’s ratification of the American Convention on Human Rights made it a State Party and as such it has, as the Inter-American Court of Human Rights stated, “(...) a legal duty (...) to use the means at its disposal to carry out a serious investigation of violations committed within its jurisdiction, to identify those responsible, to impose the appropriate punishment and to ensure the victim adequate compensation.” In reference to Article 1 of the Convention, the Court added that “if the State apparatus acts in such a way that the violation goes unpunished (...) the State has failed to comply with its duties to ensure the free and full exercise of those rights to the persons within its 329 jurisdiction.” 322. Once the amnesty law came into effect, the Commission noted in its 1994 Report on the Human Rights Situation in El Salvador that “regardless of any necessity that the peace negotiations might pose and irrespective of purely political considerations, the very sweeping General Amnesty Law passed by El Salvador’s Legislative Assembly constitutes a violation of the international obligations it undertook when it ratified the American Convention on Human Rights, because it (...) applies to crimes against humanity, and 330 because it eliminates any possibility of obtaining adequate pecuniary compensation, primarily for victims.” 323. The Commission has also taken the opportunity to address the various amnesties in El Salvador in the context of individual cases. For example, in the case of the Massacre of Las Hojas, the Commission declared that: Decree Nº 805, passed by the Legislative Assembly on October 27, 1987, provides in that part pertinent to the present case, in Article 1 that “Full and absolute amnesty is granted in favor of all persons, whether nationals or foreigners, who have participated directly or indirectly or as accomplices, in the Commission of political crimes or common crimes linked to political crimes or common crimes in which the number of persons involved is no less than twenty, committed on or before October 22 current year”; and that as a result, the passage of the amnesty, even after an arrest warrant had been issued to Armed Forces officers, legally eliminated the possibility of an effective investigation and the prosecution of the responsible parties, as well as proper compensation for the victims and their next-of331 kin by reason of the civil liability for the crime committed. 329 Note from the IACHR, addressed to the State of El Salvador on 26 March 1993. Mentioned in: IACHR. Report on the Situation of Human Rights in El Salvador. 199. 11 February 1994. Chapter II.4 330 IACHR. Report on the Situation of Human Rights in El Salvador. 199. 11 February 1994. Chapter II.4. 331 IACHR. Report No. 26/92. Case 10.287. Massacre of Las Hojas. 24 September 1992. Para. 11.