28 A practical guide to the Istanbul Protocol – for lawyers Upon receipt of a complaint, the competent authority should categorise and process it and determine whether, in appropriate cases, it reveals police misconduct that warrants an investigation, and if so, whether the misconduct amounts to a criminal of113 fence or to a breach of discipline only. In the absence of a complaint, the competent investigating authorities have an obligation to proceed with an investigation ex officio (without a formal complaint) whatever the origin of the suspicion that an act of torture has been committed.114 If these assessments reveal that the misconduct gives rise to a criminal offence, a criminal investigation should in principle be opened and the case should be assigned to the responsible investigation department or prosecution service which would direct the investigations. Police authorities may initiate disciplinary proceedings, which run parallel to criminal investigations. Most police authorities have internal systems for investigating such complaints, which usually operate independently of the standard criminal investigation process.115 If there is a serious case amounting to torture then criminal pro116 ceedings should be brought. As an alternative to an investigation by a police investigation department or by the public prosecutor, the matter may be passed on or made directly to an independent complaints body. There is a wide range of such institutions such as police complaints authorities, ombudsmen and national human rights commissions. Police complaints authorities are usually established to ensure effective investigations of police misconduct and to introduce an independent public element into complaint procedures in order to instil public confidence. The strongest bodies are those that are competent to receive and investigate complaints against the police directly. In some cases these bodies are able to investigate complaints about torture indepen- dently, using similar powers as the police, and recommend prosecution or disciplinary measures to the competent body.117 An alternative category of police complaints authority includes organisations which are generally confined to reviewing investigations by 118 the police. National human rights commissions (NHRCs), which have been set up in many countries,119 may be able to investigate human rights violations on their own motion or may be mandated to carry out initial investigations into human rights violations with the possibility of submitting conclusions to the competent investigator. Many NHRCs may only receive complaints without having the power to conduct independent investigations.120 Where investigations are carried out, it will not be on a criminal basis and after inquiry NHRCs often may only recommend to the government that prosecution proceedings are initiated.121 c. Purpose of the investigation The purpose of an investigation should be “to establish the facts relating to alleged incidents of torture, with a view to identifying those responsible and facilitating their prosecution, or for use in the context of other procedures designed to obtain redress for 122 victims”. According to the Istanbul Protocol, an investigation “must, at a minimum, seek to: • Obtain statements from the victims of alleged torture • Recover and preserve evidence, including medical evidence, related to the alleged torture to aid in any potential prosecution of those responsible • Identify possible witnesses and obtain statements from them concerning the alleged torture • Determine how, when and where the incidents occurred as well as any pattern