33 individuals.61 This is not contrary to the right of the victims of human rights violations or their families to be heard during investigation and court proceedings as well as to actively participate in such proceedings.62 94. Such investigation must be conducted using all legal means available and should be aimed at establishing the truth and conducting the investigation, search, arrest, trial, and punishment of all masterminds and actual perpetrators of the crimes, especially when State officials are or may be involved.63 95. In order for a death investigation to be effective, it is essential that the persons in charge of such investigation be independent, de jure and de facto, of the ones involved in the case.64 This requires not only hierarchical or institutional independence, but also actual independence.65 96. In this sense, based on the United Nations Manual on the Effective Prevention and Investigation of Extra-legal, Arbitrary and Summary Executions, this Court has specified the guiding principles that must be observed when a death incident is deemed to have been the result of an extrajudicial execution. The State authorities conducting an investigation shall, inter alia, a) identify the victim; b) collect and preserve evidence related to the death in order to assist with any investigation; c) identify possible witnesses and obtain testimonies in relation to the death under investigation; d) determine the cause, manner, place and time of death, as well as any pattern or practice which may have brought about such death, and e) distinguish between natural death, accidental death, suicide and homicide. In addition, it is necessary that a thorough investigation of the crime scene be conducted and rigorous autopsies and analyses of human remains be performed by competent professionals, using the best available procedures.66 97. Any deficiency or fault in the investigation affecting the ability to determine the cause of death or to identify the actual perpetrators or masterminds of the crime will constitute failure to comply with the obligation to protect the right to life.67 98. In the instant case, the Court notices significant omissions in the investigation despite the need to collect and preserve the evidence. The only official document 61 Cf. Case of the Pueblo Bello Massacre, supra note 6, para. 144; Case of the “Mapiripán Massacre”, supra note 1, para. 219; and Case of the Moiwana Community, supra note 59, para. 146. In the same regard, cf. Eur.C.H.R., Nachova and others v. Bulgaria [GC], supra note 46, para. 111. 62 Cf. Case of the Pueblo Bello Massacre, supra note 6, para. 144; Case of the “Mapiripán Massacre”, supra note 1, para. 219; and Case of the Moiwana Community, supra note 59, para. 147. 63 Cf. Case of the Pueblo Bello Massacre, supra note 6, para. 143; Case of the “Mapiripán Massacre”, supra note 1, para. 237; and Case of the Moiwana Community, supra note 59, para. 203. 64 Cf. Case of Durand and Ugarte. Judgment of August 16, 2000. Series C No. 68, paras. 125 and 126; and Eur.C.H.R., Nachova and others v. Bulgaria [GC], supra note 46, para. 112. 65 Cf. Eur.C.H.R., Hugh Jordan v. the United Kingdom, supra note 58, para. 106. 66 Cf. Case of the Pueblo Bello Massacre, supra note 6, para. 177; Case of the “Mapiripán Massacre”, supra note 1, para. 224; and Case of the Moiwana Community, supra note 59, para. 149; in the same regard see also Manual on the Effective Prevention and Investigation of Extra-Legal, Arbitrary and Summary Executions, United Nations, Doc. E/ST/CSDHA/.12 (1991). 67 Cf. Eur.C.H.R., Nachova and others v. Bulgaria [GC], supra note 46, para. 113; and Eur.C.H.R., Kelly and others v. the United Kingdom, No. 30054/96, Judgment of May, 2001, para. 96.