38 131. Moreover, although the Court appreciates the re-opening of the Investigation in 2009, it underscores that the request to re-open the Investigation demonstrated the need to adopt investigative measures to clarify the facts; some of these have been noted in this section. In this regard, the Public Prosecutor’s Office considered that the following measures, among others, should be taken: (i) the testimony of Vanderlei Garibaldi and two of his brothers-in-law who witnessed the events should be heard; (ii) the testimony of other individuals from the camp who were present during the eviction operation and also of Giovani Braun should be received; (iii) police clerk Ribeiro should be heard in order to clarify the information he provided to the investigation; (iv) the testimony of Morival Favoreto and Ailton Lobato should be received and they should be asked where they were at the time of the crime, “emphasizing that [the receipt from the doctor’s visit] refers to a date prior to the facts; namely 25/11/1998,” and (v) the seized weapon, together with the confiscated cartridges and bullets, should be located and sent for ballistic comparison. 132. Based on the foregoing, the Court finds that the absence of a State response is a determinant element when assessing whether there has been a failure to comply with Articles 8(1) and 25(1) of the American Convention, because this is directly related to the principle of effectiveness that should characterize the development of investigations.122 In the instant case, the errors and omissions noted by the Court show that the State authorities did not act with due diligence or in accordance with the obligations arising from the said articles concerning the obligation to investigate. C(ii) Duration of the investigation 133. The Court has indicated that the right of access to justice must ensure the right of the presumed victims or their next of kin that everything necessary should be done to discover the truth of what happened and to punish those responsible, within a reasonable time.123 In principle, the absence of reasonableness in the duration of the investigation constitutes, in itself, a violation of judicial guarantees.124 In this regard, the Court has taken into account four elements to determine the reasonableness of the time: (a) the complexity of the matter; (b) the procedural activity of the interested party; (c) the conduct of the judicial authorities,125 and (d) the effect on the legal situation of the person involved in the proceeding.126 134. The Court notes that the delay in conducting the investigation cannot be justified based on the complexity of the matter. Indeed, in the instant case, there was a single act that took place in front of numerous witnesses, involving just one clearly identified victim. Thus, from the start of the Investigation, evidence might have existed about the possible authorship and motivation for the act that could have guided the procedure and the measures taken. 122 Cf. Case of García Prieto, supra note 59, para. 115; Case of Escher et al., supra nota 9, para. 206, and Case of Ticona Estrada et al., supra note 98, para. 79. 123 Cf. Case of Bulacio v. Argentina. Merits, reparations and costs. Judgment of September 18, 2003. Series C No. 100, para. 114; Case of Kawas Fernández, supra note 14, para. 112, and Case of Ticona Estrada et al., supra note 98, para. 79. 124 Cf. Hilaire, Constantine and Benjamin et al. v. Trinidad and Tobago. Merits, reparations and costs. Judgment of June 21, 2002. Series C No. 94, para. 145; Case of Valle Jaramillo et al., supra note 95, para. 154, and Case of Heliodoro Portugal, supra note 13, para. 148. 125 Cf. Genie Lacayo v. Nicaragua. Merits, reparations and costs. Judgment of January 29, 1997. Series C No. 30, para. 77; Case of Kawas Fernández, supra note 14, para. 112, and Case of Valle Jaramillo et al., supra nota 95, para. 155. 126 Cf. Case of Valle Jaramillo et al., supra note 95, para. 155, and Case of Kawas Fernández, supra note 14, para. 112.