40 In this case, the Court considers that it is not necessary to examine this element to determine whether the duration of the Investigation into the death of Mr. Garibaldi was reasonable. 139. Based on these findings, the Court concludes that the term of more than five years taken merely by the investigation stage of the domestic procedure goes far beyond a time that could be considered reasonable for the State to conduct the corresponding investigative measures and constitutes a denial of justice to the detriment of the next of kin of Sétimo Garibaldi. * * * 140. The Inter-American Court concludes that the State authorities did not act with due diligence in the investigation into the death of Sétimo Garibaldi, which also exceeded a reasonable time. Consequently, the State violated the rights to judicial guarantees and protection established in Articles 8(1) and 25(1) of the American Convention, in relation to Article 1(1) thereof, to the detriment of Iracema Garibaldi, Darsônia Garibaldi, Vanderlei Garibaldi, Fernando Garibaldi, Itamar Garibaldi, Itacir Garibaldi and Alexandre Garibaldi. 141. The Court cannot fail to express its concern owing to the serious errors and delays in the Investigation in the instant case, which affected the victims who are members of a group that is considered vulnerable. As this Court has indicated, impunity encourages the chronic repetition of human rights violations.129 VII ARTICLE 28 (FEDERAL CLAUSE) 130 IN RELATION TO ARTICLES 1(1) AND 2 OF THE AMERICAN CONVENTION 142. The Commission indicated that, irrespective of the internal distribution of competences, in compliance with Article 28 of the American Convention, Brazil should have adopted: (1) adequate measures to ensure that Sétimo Garibaldi was not murdered by an armed group at the service of landowners of the state of Paraná, who were attempting to perform a clandestine eviction, as well as to provide his next of kin with an effective investigation into the facts, the prosecution and punishment of those responsible, and adequate civil compensation, and (ii) effective measure to avoid the proliferation of armed groups carrying out violent clandestine evictions. The federal form of government seeks to grant greater autonomy and wide-ranging administrative scope to the states that make up the Union, while the Federal State conserves some of the basic functions. According to article 23(1) of the Federal Constitution, the Union, the states, the federal district, and the municipalities, together, have the obligation to uphold the Constitution and the law. Given that “the mechanisms were ineffective, the State […] cannot argue its lack of responsibility at any level.” The federal units, as parts of the Federal State, are equally bound by the 129 Cf. Case of the “White Van” (Paniagua Morales et al.), supra note 31, para. 173; Case of Kawas Fernández, supra note 14, para. 190, and Case of Valle Jaramillo et al., supra note 95, para. 100. 130 Article 28 of the American Convention establishes: 1. Where a State Party is constituted as a federal state, the national government of such State Party shall implement all the provisions of the Convention over whose subject matter it exercises legislative and judicial jurisdiction. 2. With respect to the provisions over whose subject matter the constituent units of the federal state have jurisdiction, the national government shall immediately take suitable measures, in accordance with its constitution and its laws, to the end that the competent authorities of the constituent units may adopt appropriate provisions for the fulfillment of this Convention. […]