ff IPCB to have responsibility for the investigation of an incident, recorded in the absence of a complaint, which may be carried out by IPCB or police investigators. Adequacy 67. The adequacy principle has been developed to ensure that police complaints investigations are effective and capable of bringing offenders to justice. 68. Adherence to the rule of law requires that a complaints investigation into the conduct of an officer must be carried out in accordance with the same procedures, including safeguards for the officer complained against, that apply for a member of the public suspected of wrongdoing. 69. Requirements of a thorough and comprehensive police complaints investigation include: ff taking a full and accurate statement from the complainant covering all of the circumstances of their complaint;231 ff making reasonable efforts to trace witnesses, including members of the public232 and police officers,233 for the purpose of obtaining full and accurate statements;234 ff where issues of criminal culpability may arise, interviewing police officers accused or suspected of wrongdoing as a suspect entitled to due process safeguards,235 and not allowing them to confer with colleagues before providing an account; ff making reasonable efforts to secure, gather and analyse all of the forensic236 and medical evidence;237 231. See, for example, Cobzaru v. Romania (Application no. 48254/99), Judgment 26 July 2007, § 71. 232. See, for example, Ognyanova v. Bulgaria (Application no. 46317/99), Judgment 23 February 2006, § 110. 233. See, for example, Velikova v. Bulgaria (Application no. 41488/98), Judgment 18 May 2000, § 79. 234. See, for example, Assenov v. Bulgaria (90/1997/874/1086), Judgment 28 October 1998, § 103. 235. See, for example, Ramsahai v. The Netherlands (Application no. 52391/99), Judgment 15 May 2007, § 330. 236. See, for example, Ramsahai v. The Netherlands (Application no. 52391/99), Judgment 15 May 2007, § 329. 237. See, for example, Aksoy v. Turkey (100/1995/606/694), Judgment 18 December 1996, § 56. Appendices ► Page 97