62 expeditious justice, adversarial defense, effective recourse, implementation judgment, and the proportionality of punishment, among other principles. of the 194. States have the duty to initiate ex officio, without delay, and with due diligence, a serious, impartial and effective investigation designed to fully establish responsibility for violations200. In order to achieve this objective, it is necessary, inter alia, that an effective system exist to protect judicial branch officials, as well as victims and their next of kin. Moreover, when necessary, it is important to expose the existence of complex criminal structures and their connections which made the violations possible. In this sense, dispositions that impede the investigation and punishment of those responsible for grave violations are inadmissible.201 195. In cases of grave violations of human rights, the positive obligations inherent in the right to truth demand the adoption of institutional structures that permit this right to be fulfilled in the most suitable, participatory, and complete way. These structures should not impose legal or practical obstacles that make them illusory. The Court emphasizes that the satisfaction of the collective dimension of the right to truth requires a legal analysis of the most complete historical record possible. This determination must include a description of the patterns of joint action and should identify all those who participated in various ways in the violations and their corresponding responsibilities. Moreover, the investigation must be undertaken by the State as its own legal obligation, and not as a superficial administration of private interests, which depends upon the procedural initiative of the victims or their next of kin, or upon the production of evidence by private parties.202 With regard to the participation of the victims, the State should guarantee that at every stage of the proceedings the victims have the opportunity to present their concerns and evidence, and that these be completely and seriously analyzed by the authorities before determining the facts, responsibility, penalties, and reparations.203 196. With regard to the principle of proportionality of the punishment, the Court deems it appropriate to emphasize that the punishment which the State assigns to the perpetrator of illicit conduct should be proportional to the rights recognized by law and the culpability with which the perpetrated acted, which in turn should be established as a function of the nature and gravity of the events.204 The punishment should be the result of a judgment issued by a judicial authority. Moreover, in identifying the appropriate punishment, the reasons for the punishment should be determined. With regard to the principle of lenity based upon the existence of an earlier more lenient law, this principle should be harmonized with the principle of proportionality of punishment, such that criminal justice does not become 200 Cf. Case of Vargas Areco, supra note 8, para. 76 and 77; Case of Ximenes Lopes, supra note 24, para. 148; and Case of the Ituango Massacres, supra note 15, para. 296. 201 Cf. Case of Molina Theissen. Reparations. Judgment of July 3, 2004. Series C No. 108, para. 84; Case of Myrna Mack Chang, supra note 167, para. 276; and Case of Barrios Altos. Judgment of March 14, 2001. Series C No. 75, para. 41. 202 Cf. Case of Goiburú et al., supra note 11, para. 117; Case of the Pueblo Bello Massacres, supra note 12, para. 144; and Case of Baldeón García, supra note 112, para. 146. 203 Cf. Case of Ximenes Lopes, supra note 24, para. 193; Case of the Ituango Massacre, supra note 15, para. 296; and Case of Baldeón García, supra note 112, para. 146. 204 Cf. Case of Vargas Areco, supra note 8, para. 108; Case of Raxcacó Reyes. Judgment of September 15, 2005. Series C No. 133, para. 70 and 133; and Case of Hilaire, Constantine and Benjamin et al., supra note 33, para. 102.