83 as to prevent them and avoid them remaining unpunished. Consequently, faced with the gravity of certain offenses, the norms of international customary and treatybased law establish the obligation to prosecute those responsible. This acquires particular relevance in cases such as this, because the facts occurred in a context of the systematic violation of human rights – both offenses constituting crimes against humanity – and this gives rise to the States’ obligation to ensure that such conduct is criminally prosecuted and the perpetrators punished. 129. Having established the broad scope of the international obligations erga omnes against the impunity of grave human rights violations, the Court reiterates that, in the terms of Article 1(1) of the American Convention, the States are obliged to investigate human rights violations and prosecute and punish those responsible. 130. The full exercise of justice in this type of case imposed on Paraguay the compulsory obligation to have requested the extradition of the accused promptly and with due diligence. Consequently, according to the general obligation of guarantee established in Article 1(1) of the American Convention, Paraguay should adopt the necessary measures, of a diplomatic and judicial nature, to prosecute and punish all those responsible for the violations committed, which includes furthering the corresponding extradition requests by all possible means. The inexistence of extradition treaties does not constitute a motive or justification for failing to institute a request of this type. 131. Consequent with the foregoing, given the nature and gravity of the facts, particularly since they occurred in a context of systematic human rights violations, the need to eliminate impunity establishes an obligation for the international community to ensure inter-State cooperation to this end. Impunity will not be eliminated unless it is accompanied by the determination of the general responsibility (of the State) and the specific criminal responsibility (of its agents or of individuals), which are complementary. Access to justice is a peremptory norm of international law and, as such, gives rise to obligations erga omnes for the States to adopt all necessary measures to ensure that such violations do not remain unpunished, either by exercising their jurisdiction to apply their domestic law and international law to prosecute and, when applicable, punish those responsible, or by collaborating with other States that do so or attempt to do so. 132. Hence, extradition is an important instrument to this end. The Court therefore deems it pertinent to declare that the States Parties to the Convention should collaborate with each other to eliminate the impunity of the violations committed in this case, by the prosecution and, if applicable, the punishment of those responsible. Furthermore, based on these principles, a State cannot grant direct or indirect protection to those accused of crimes against human rights by the undue application of legal mechanisms that jeopardize the pertinent international obligations. Consequently, the mechanisms of collective guarantee established in the American Convention, together with the regional86 and universal87 international obligations on 86 Cf. Charter of the Organization of American States, Preamble and article 3(e); Inter-American Convention to Prevent and Punish Torture; Inter-American Convention on Forced Disappearance of Persons; and Resolution No. 1/03 of the Inter-American Commission on Human Rights on Trial for International Crimes.