17 powers set forth in Article 45 of its Rules of Procedure, the Court or its President may ask the parties for additional items as evidence to facilitate adjudication, without this constituting a new opportunity to expand or complement the pleadings, unless the Court explicitly allows this.8 73. The Court has stated before, with regard to receiving and assessing evidence, that the proceedings before it are not subject to the same formalities as court proceedings under domestic law, and that inclusion of certain items in the body of evidence must be done paying special attention to the circumstances of the specific case and bearing in mind the limits established to ensure respect for legal certainty and procedural balance among the parties. The Court has also taken into account that international jurisprudence, deeming that international courts have the authority to assess and appraise evidence in accordance with the rules of competent analysis, has always avoided a rigid determination of the quantum of evidence necessary as grounds for a decision. This criterion is especially valid with regard to international human rights courts, which –to establish the international responsibility of a State for violations of the person’s rights- enjoy broad flexibility in the assessment of the evidence tendered before them regarding the pertinent facts, in accordance with the rules of logic and based on experience.9 74. On the aforementioned basis, the Court will now examine and assess the items that constitute the body of evidence in the instant case. A) DOCUMENTARY EVIDENCE 75. As part of the documentary evidence submitted by the parties, the representatives forwarded the statements by next of kin of the alleged victims and of Luis Guillermo Pérez, as well as the expert opinions of expert witnesses Robin Kirk and Ana Deutsch, in response to the Order issued by the President on January 28, 2005 (supra para. 25). The Court will now summarize those statements. a) María Teresa Pinzón López, sister of Luis Eduardo, Enrique, José Alberto and Jorge Pinzón López Her mother lived in Mapiripán with her brothers, her sister Luz Mery, the daughter and her spouse. Although she got along very well with her brothers, she “did not visit them because [she] was afraid.” She does not recall very well the day she learned what happened to her brothers. It is terrible to remember what happened and try not to think, because “losing a brother is very hard, but losing them all is terrible.” Her mother, Teresa López de Pinzón, “became ill [due to] a stroke [and] half her body was paralyzed. She also suffered heart problems [and] a heart attack.” Losing her four sons “is what killed [her] mother[, who] cried like a child.” Luz Mery, her older sister, who also lost her common-law spouse, “was very nervous [and] was not well psychologically, that destroyed her [and now] she is very depressed;” her personal appearance changed very much, as she saw everything, and that has “damaged and destroyed” her. Nothing is the same anymore in the family, and they live far away. She is afraid to inquire whether those responsible for the facts have 8 See Case of Acosta Calderón, supra note 7, para. 42; Case of Yatama, supra note 7, para. 107, and Case of Fermín Ramírez, supra note 7, para. 44. 9 See Case of Acosta Calderón, supra note 7, para. 41; Case of Yatama, supra note 7, para. 108, and Case of Fermín Ramírez, supra note 7, para. 45.