GIULIANI AND GAGGIO v. ITALY JUDGMENT 79 Others, cited above, § 161). The State must therefore ensure, by all means at its disposal, an adequate response – judicial or otherwise – so that the legislative and administrative framework set up to protect the right to life is properly implemented and any breaches of that right are repressed and punished (see Zavoloka v. Latvia, no. 58447/00, § 34, 7 July 2009). 299. The State's obligation to carry out an effective investigation has in the Court's case-law been considered as an obligation inherent in Article 2, which requires, inter alia, that the right to life be “protected by law”. Although the failure to comply with such an obligation may have consequences for the right protected under Article 13, the procedural obligation of Article 2 is seen as a distinct obligation (see İlhan v. Turkey [GC], no. 22277/93, §§ 91-92, ECHR 2000-VII; Öneryıldız v. Turkey [GC], no. 48939/99, § 148, ECHR 2004-XII; and Šilih v. Slovenia [GC], no. 71463/01, §§ 153-154, 9 April 2009). It can give rise to a finding of a separate and independent “interference”. This conclusion derives from the fact that the Court has consistently examined the question of procedural obligations separately from the question of compliance with the substantive obligation (and, where appropriate, has found a separate violation of Article 2 on that account) and the fact that on several occasions a breach of a procedural obligation under Article 2 has been alleged in the absence of any complaint as to its substantive aspect (see Šilih, cited above, §§ 158-159). 300. For an investigation into alleged unlawful killing by State agents to be effective, it may generally be regarded as necessary for the persons responsible for and carrying out the investigation to be independent from those implicated in the events (see, for example, Güleç, cited above, §§ 81-82, and Oğur, cited above, §§ 91-92). This means not only a lack of hierarchical or institutional connection but also a practical independence. What is at stake here is nothing less than public confidence in the State's monopoly on the use of force (see Hugh Jordan, cited above, § 106; Ramsahai and Others [GC], cited above, § 325; and Kolevi v. Bulgaria, no. 1108/02, § 193, 5 November 2009). 301. The investigation must also be effective in the sense that it is capable of leading to a determination of whether the force used was or was not justified in the circumstances (see, for example, Kaya v. Turkey, 19 February 1998, § 87, Reports 1998-I) and of identifying and – if appropriate – punishing those responsible (see Oğur, cited above, § 88). This is not an obligation of result, but of means. The authorities must take whatever reasonable steps they can to secure the evidence concerning the incident, including, inter alia, eyewitness testimony, forensic evidence and, where appropriate, an autopsy which provides a complete and accurate record of injury and an objective analysis of the clinical findings, including the cause of death (as regards autopsies, see, for example, Salman v. Turkey [GC], no. 21986/93, § 106, ECHR 2000-VII; on the subject of witnesses,