38. To assess how far the requirement to exhaust remedies available under domestic law has been met, the Commission must determine which is the appropriate remedy that should be exhausted in the circumstances, understanding this as that remedy which is able to solve the juridical situation that has been infringed. In cases of alleged arbitrary infringements of the right to life, the appropriate remedy is the criminal investigation and proceedings brought and pursued by the State in order to identify and punish those responsible. 39. In relation to the unwarranted delay, the Commission examines the circumstances and makes a case-by-case evaluation in order to decide whether or not there has been an unwarranted delay. As a general rule, the Commission states that “a criminal investigation should be carried out promptly to protect the interests of the victims and to preserve evidence.” 10 To determine whether or not an investigation has been carried out “promptly”, the Commission must evaluate a series of factors such as the time elapsed since the offense was committed, whether the investigation has progressed beyond the initial stages, the steps taken by the authorities, and the complexity of the case. 11 40. In this case, the petitioners allege there has been an unwarranted delay in the investigation and therefore that they have been denied justice under domestic law. They state that there has been negligence and omission 12 on the part of the Public Prosecutor’s Office, which possesses exclusive authority to initiate investigations and bring criminal proceedings for so-called criminal cases in view of the fact that more than three years after the event that gave rise to the petition the case is still in its preparatory stage and no criminal charges have been brought. On the basis of the information provided by the petitioners and unchallenged by the State, it appears that the investigations have not progressed since September 2004 in spite of the fact that Mrs. Yelitze de Castillo has played an active role and even asked for proceedings to be undertaken. 41. Taking the above into account, the Commission considers that in the instant case an unwarranted delay has taken place in the criminal investigation and that consequently, according to Article 46(2)(c), the petitioners are exonerated from the requirement to exhaust the remedies available under domestic law. 42. The Commission reaffirms that citing exceptions to the rule of exhaustion of remedies available under domestic law enshrined in Article 46(2) of the Convention is closely linked to the definition of possible violations of certain rights described therein, such as the right to judicial guarantees. However, Article 46(2) of the American Convention, by its nature and object, is autonomous in content, vis á vis the Convention’s substantive norms. Therefore, a decision on whether the exceptions to the rule of exhaustion of remedies available under domestic law enshrined in Article 46(2) can be applied to the case in question must be established prior to, and separate from, an examination of the merits of the case because it relies on a different standard of judgment than the one that determines a violation of Articles 8 and 25 of the Convention. It should be pointed out that the causes and effects that have prevented the exhaustion of remedies available under domestic law in the present case will be examined, as far as they are relevant, in the Report adopted by the Commission on the merits of the case, in order to establish whether it indeed deals with real violations of the American 10 IACHR, Report No. 16/02, Petition 12.331, Servellón García, Honduras, Admissibility, paragraph 31 (February 27, 2002). 11 IACHR, Report No. 130/99, Petition 11.740, Victor Manuel Oropeza, Mexico, paragraphs 30-32. 12 The petitioners state that: […]The steps taken by the Investigating Office (Fiscalía) have tended basically to establish thecorpus delicti, such as a visual examination of the scene of the event; the visual inspection of the car driven by Joe Luis Castillo; the visual examination of his body; the certificate for the removal of the body; the taking of verbal descriptions for identification; the forensic examination of the minor Luís Cesar Castillo and of Yelitze Moreno de Castillo.[…]Even when the Public Prosecutor’s Office interviewed those in the vicinity of the events, some of whom, at the time, reported valuable observations, these were not used subsequently to feed into and activate lines of investigation. […]Equally, even though the Public Prosecutor’s Office carried out two photographic examinations with Yelitze, it has not checked the evidence by comparing the ballistic studies based on the bullets that were found against weapons that have been similarly seized from persons killed during alleged confrontations with police, nor against expert analysis of the legal examination made of the bullets found at the scene of the events. 7