21 l) Expert Opinion of Peter van Reenen, expert witness The expert witness stated that the main conclusion from past evaluation experience is that, in all emergency situations, including prison riots, the quality of operations depends on the level of preparation for such emergencies. The expert witness pointed out that “lack of preparation inevitably leads to uncoordinated and unplanned individual action on the part of prison officers.” Moreover, he stated that “the most likely outcome of poor preparation is chaotic management of the riot and absence of restrictions.” According to the expert witness, planning includes the implementation of a policy and a strategy to control disturbances, riots and hostage-taking, which should include: i) the organization of operations, ii) the definition of responsibilities for action and lines of command, iii) the general principles and guidelines for operations, and iv) the guidelines and standards for the use of force. In his opinion, each one of these elements should be documented in a reference manual. Therefore, training in emergency situations increases the potential to control the situation in an effective manner. The expert witness concludes that there is nothing in the documents made available to him to suggest that the staff within the prison service or the armed forces have developed emergency action plans; even worse, preparation and planning regarding measures to control prison riots are non-existent. “If, in fact, no action plans were developed, this would be one of the main factors shaping the way the events unfolded and the level of violence and force used” on November 27, 1992. In addition, the fact that there were “80 officers [...] in charge of supervising 3600” inmates shows that the detention center was understaffed, and that “the use of force is probably the only way in which a small number of guards can control inmates.” Furthermore, the expert witness stated that, in his experience, the fact that access to the Detention Center facilities was denied to public prosecutors and the manner in which investigations were conducted, led him to conclude that “those involved in the conflict tried to conceal the facts.” B) m) Statements made at a public hearing Statement of Giovanni Gaviria-Velásquez, brother of Néstor Luis Gavidia-Velásquez On December 2, 1992, he learned that his brother had died. Before that date, he and his relatives had been relentlessly looking for his brother. They visited several hospitals in and around the capital city, and they were given no information on whether he was hurt, dead or still in prison. The next of kin of the deceased inmates had to go through a lot of hassle to find the bodies and give them proper burial. The witness tried to obtain information from the