– examination of custody records, decisions, case files and other documentation related to the relevant incident. 4.2.3 Evidence should be assembled and investigations conducted in conformity with domestic procedural rules. Procedural failures that contribute to the collapse of subsequent legal proceedings constitute failures to take all reasonable steps to secure evidence concerning the incident. 4.2.4 Information and evidence relating to ill-treatment must be assessed in a thorough, consistent and objective manner. 4.2.5 Investigations should be comprehensive in scope. 4.3 Promptness 4.3.1 Investigations and eventual legal proceedings must be conducted in a prompt and reasonably expeditious manner. 4.3.2 Promptness is a key to maintaining public confidence. 4.4 Competence 4.4.1 Investigative bodies must have full competence to establish the facts of the case and to identify and punish those responsible where necessary. 4.4.2 No legal or practical obstacles should impede investigations. 4.4.3 Investigative bodies should have the power to suspend from service or from particular duties persons under investigation. 4.4.4 Investigative bodies should be able to apply protective measures to ensure that alleged victims and other persons involved in the investigation are not intimidated or otherwise dissuaded from participating in investigations. 4.5 Victim involvement and public scrutiny 4.5.1 Alleged victims of ill-treatment or their representatives must be involved in investigative procedures to the extent necessary to safeguard their legitimate interests. Victims should be entitled to request specific steps to be taken and to participate in specific investigative actions, where appropriate. They should be regularly informed as to the progress of investigations and all relevant decisions made. They should be provided with legal aid, if necessary, and be able to challenge actions or omissions of investigating authorities by means of a public and adversarial judicial review procedure. 4.5.2 In particularly serious cases, a public inquiry may be required in order to satisfy this requirement. Effective investigation of ill-treatment – Guidelines ► Page 14