111 Part 3 • The fact that a suspect does not confess does not negate the value of the interview. Depending on the laws of evidence and criminal procedure applicable in the jurisdiction, lies, evasions or a failure to explain or to contradict facts can be just as damning to a suspect as a full confession. Allowing the interviewee to spin these lies and evasions is not a waste of time; and • Where video or audio recording facilities exist they should be used, without exception, to protect both the suspect and the police in the same way as the presence of a lawyer does. Confessions or other significant statements made by the suspect that are recorded in this way cannot later be denied in court. Training in interview techniques, such as the PEACE Interview Model detailed in section 2.1.1 of the manual, benefit the effectiveness of police interviews and enhance the human rights of terrorism suspects. Investigators and those who assist them should receive comprehensive training – backed up by regular refresher training – in general investigation techniques, including the interviewing of witnesses, the gathering of physical evidence and the packaging and handling of forensic exhibits, with an emphasis on ensuring the continuity of the evidence chain. Any improvement in dealing with witnesses and forensic evidence will reduce the reliance on obtaining confessions for the purpose of securing convictions. 3.6 Prolonged Detention and Additional Questioning of Suspects In principle, the maximum length of initial police detention should be of short duration, no more than two or three days. Although it has not been uncommon in terrorism-related investigation to extend the periods of detention, either before or after charges are brought against a suspect, this must be strictly defined in domestic legislation, in compliance with international human rights standards. Such extended periods of detention usually take place in police stations, but sometimes also in special police detention facilities or in so called “investigative isolators” used in some OSCE participating States. These are usually manned by prison staff, but allow police and criminal investigators easy access. Both extended detention pending trial and the ease of access that the police may have to detainees can give rise to specific human rights concerns.