16 68. Under the law of nations, a customary law prescribes that a State that has concluded 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 Greek and Turkish populations, Advisory Opinion, 1925, PCIJ, Series B No. 10, p. 20). Accordingly, the American Convention stipulates that every State Party is to adapt its domestic laws to the provisions of that Convention, so as to guarantee the rights embodied therein. 69. This obligation of the State Party implies that the domestic legal measures must be effective. This means the State must adopt all measures necessary so that provisions contained in the Convention have full force and effect within its domestic legal system. Those measures are effective when the community, in general, adapts its conduct to conform to the principles of the Convention and when, if those principles are breached, the penalties provided for therein are effectively applied. 70. The effectiveness of laws is of fundamental importance in a legal system, as lack of effectiveness may compromise their standing as law. This Court underscored this point in the Aloeboetoe et al. Case, Reparations, when Suriname’s argument that Surinamese family law applied in the region inhabited by the Saramaca tribe was rejected by the Court because Surinamese family law was not effective in that region; the Court opted instead to apply local customary law (Aloeboetoe et al. Case, Reparations, supra 40, paragraphs 58 and 62).. 71. Argentine laws that guarantee the right to life have been violated in the instant case. Therefore, to ensure their effectiveness, Argentina must apply the provisions established for violations of those laws; in other words, it must impose the corresponding sanctions. These are the measures provided for in the American Convention and that the State must take to ensure the effectiveness of the rights and duties guaranteed under the Convention. The American Convention is a multilateral treaty whereby States parties undertake to guarantee and ensure effective exercise of the rights and freedoms guaranteed therein and to comply with the reparations ordered. Hence, the fundamental obligations that the American Convention embodies to protect the rights and freedoms enumerated in its Articles 3 to 25, is to adapt domestic laws to conform to the Convention and to make reparation, and thereby guarantee all the rights and freedoms therein upheld. 72. These obligations are of equal importance. The obligation to guarantee and ensure effective exercise is independent of and different from the obligation to make reparation. The difference lies in the following: the reparation provided for in Article 63(1) is an attempt to erase the consequences that the unlawful act may have had for the affected person, his family or close friends. Since the measure is intended to make reparations for a personal situation, the affected party has the right to waive that right. Thus, the Court could not object if an individual, particularly an adult, who was the victim of a human rights violation waived the compensation to which he or she was entitled. On the other hand, even though the aggrieved party may pardon the author of the violation of his human rights, the State is nonetheless obliged to sanction said author, except when the offense involved is prosecutable by a private party. The State’s obligation to investigate the facts and punish those responsible does not erase the consequences of the unlawful act in the affected person. Instead, the purpose of that obligation is that every State party ensure, within its legal system, the rights and freedoms recognized in the Convention.