31. The Appeals Chamber will consider these challenges in turn. At the outset, it recalls that it is within the discretion of a trial chamber to evaluate inconsistencies in the evidence, to consider whether the evidence taken as a whole is reliable and credible, and to accept or reject the fundamental features of the evidence.[1] The Appeals Chamber will defer to a trial chamber’s judgement on issues of credibility, including its resolution of disparities among different witnesses’ accounts, and will only find an error of fact if it determines that no reasonable trier of fact could have made the impugned finding.[2] Furthermore, corroboration may exist even when some details differ between testimonies, provided that no credible testimony describes the facts in question in a way which is not compatible with the description given in another credible testimony.[3]

48. The Appeals Chamber recalls that a trial chamber may rely on part of a witness’s testimony and reject other parts.[4] Furthermore, the Appeals Chamber notes that the Trial Chamber only relied on Witness SLA’s testimony where corroborated.[5] The Trial Chamber was therefore entitled to disregard Witness SLA’s claim of torture and still rely on his evidence with respect to the 25 April and 11 May Killings.

154. Regarding Setako’s contention that the Trial Chamber erred in its reasoning, the Appeals Chamber recalls that the task of weighing and assessing evidence lies primarily with the trier of fact.[6] Therefore, the Appeals Chamber must give a margin of deference to a finding of fact reached by a trial chamber.[7] It will only interfere where no reasonable trier of fact could have reached the same finding or where the finding is wholly erroneous.[8]

222. Setako’s submission that the Trial Chamber erred in dismissing his evidence for lack of corroboration due to contradictions in the testimonies of Witnesses SLA and SAT is unclear. If Setako claims that the Trial Chamber was compelled to accept his testimony because Witnesses SLA’s and SAT’s testimonies deviated from each other, the Appeals Chamber disagrees. The Appeals Chamber recalls that a trial chamber has the discretion to decide on the weight, if any, to accord to a piece of evidence, regardless of whether or not that evidence is corroborated.[9] This discretion is not affected by purported inconsistencies in other evidence.

145. The Appeals Chamber recalls that a Trial Chamber may enter a conviction on the “basis of a single witness, although such evidence must be assessed with the appropriate caution, and care must be taken to guard against the exercise of an underlying motive on the part of the witness.”[1] The Appeals Chamber further recalls that “a Trial Chamber should at least briefly explain why it accepted the evidence of witnesses who may have had motives or incentives to implicate the accused; in this way, a Trial Chamber shows its cautious assessment of this evidence.”[2] [see also para. 242 of the Appeals Judgement]

219. The Appeals Chamber recalls that a Trial Chamber is at liberty to rely on the evidence of a single witness when making its findings.[3] The testimony of a single witness may be accepted without the need for corroboration, even if it relates to a material fact.[4] […]

45. The Appeals Chamber also rejects Ndahimana’s contention that as a matter of law witnesses who require corroboration cannot corroborate one another.[1] In the Appeals Chamber’s view, a finding that a witness’s evidence is not sufficiently credible or reliable to be relied upon on its own, and therefore needs corroboration, does not amount to a finding that the witness cannot be relied upon at all, but merely denotes the adoption of a cautious approach by the trial chamber in its evidentiary assessment of the evidence. Absent any contrary finding, a trial chamber’s decision to ultimately rely upon the cumulative evidence of witnesses whose evidence required corroboration reflects the trial chamber’s determination that, taken as whole, the evidence was sufficiently credible and reliable. This factual determination is an exercise of the trial chamber’s discretionary power in assessing the credibility of witnesses and in determining the weight to be accorded to their evidence in which the Appeals Chamber will only interfere where no reasonable trier of fact could have reached the same finding or where the finding is wholly erroneous.[2]  

21. The Appeals Chamber recalls that a Trial Chamber has full discretion to assess the appropriate credibility and weight to be accorded to the testimony of a witness;[1] corroboration is one of many potential factors relevant to this assessment.[2] A Trial Chamber retains discretion to decide, in the circumstances of each case, whether corroboration of evidence is necessary and to rely on uncorroborated, but otherwise credible, witness testimony.[3]

[…]

24. Nevertheless, the Appeals Chamber recalls that two prima facie credible testimonies need not be identical in all aspects or describe the same fact in the same way in order to be corroborative.[4] Every witness presents what he has seen from his own point of view at the time of the events, or according to how he understood the events recounted by others.[5] It follows that corroboration may exist even when some details differ between testimonies, provided that no credible testimony describes the facts in question in a way which is not compatible with the description given in another credible testimony.[6]

62. Neither the Statute nor the Rules oblige a Trial Chamber to require medical reports or other scientific evidence as proof of a material fact.  Similarly, the testimony of a single witness on a material fact does not require, as a matter of law, any corroboration.  The only Rule directly relevant to the issue at hand is Rule 89.  In particular, sub-Rule 89(C) states that a Chamber “may admit any relevant evidence which it deems to have probative value”, and sub-Rule 89(D) states that a Chamber “may exclude evidence if its probative value is substantially outweighed by the need to ensure a fair trial”. 

79. […] [I]t is well settled that “the testimony of a single witness on a material fact may be accepted as evidence without the need for corroboration.”[1] However, the Appeals Chamber considers that this jurisprudence cannot be interpreted to mean that a Trial Chamber cannot resort to corroboration; the Trial Chamber can do so by virtue of its discretion. […]

36.     One of the duties of a Trial Chamber is to assess the credibility of witnesses.  In discharging that duty, the Trial Chamber takes into account all the circumstances of the case.  As stated in the Aleksovski Appeal Judgement, “[w]hether a Trial Chamber will rely on single witness testimony as proof of a material fact, will depend on various factors that have to be assessed in the circumstances of each case.”[1]  It may be that a Trial Chamber would require the testimony of a witness to be corroborated, but according to the established practice of this Tribunal and of the International Criminal Tribunal for the Former Yugoslavia (ICTY), that is clearly not a requirement.[2]

37.     In the instant case, the Trial Chamber affirmed that it “may rule on the basis of a single testimony if, in its opinion, that testimony is relevant and credible.”[3] It further stated that:

[…] it is proper to infer that the ability of the Chamber to rule on the basis of testimonies and other evidence is not bound by any rule of corroboration, but rather on the Chamber’s own assessment of the probative value of the evidence before it.

The Chamber may freely assess the relevance and credibility of all evidence presented to it. The Chamber notes that this freedom to assess evidence extends even to those testimonies which are corroborated: the corroboration of testimonies, even by many witnesses, does not establish absolutely the credibility of those testimonies.[4]

38.     The Appeals Chamber is of the view that these statements correctly reflect the position of the law regarding the Trial Chamber’s discretion in assessing testimonies and the evidence before it.

203. […] Moreover, corroboration of testimonies, even by many witnesses, does not establish automatically the credibility, reliability or weight of those testimonies.[1] Corroboration is neither a condition nor a guarantee of reliability of a single piece of evidence.[2] It is an element that a reasonable trier of fact may consider in assessing the evidence. However, the question of whether to consider corroboration or not forms part of its discretion.

125. The Appeals Chamber recalls that two testimonies corroborate one another when one prima facie credible testimony is compatible with the other prima facie credible testimony regarding the same fact or a sequence of linked facts. It is not necessary that both testimonies be identical in all aspects or describe the same fact in the same way.

126. The Appeals Chamber finds that it was reasonable for the Trial Chamber to find thematic consistencies between the accounts of Witnesses BBP, BVS, and BBJ, “in particular, that Gatete came to the parish prior to 11 April, spoke to gendarmes, who witnesses recalled had guarded the parish, and also spoke to the two priests at the parish.”[3] The Appeals Chamber is of the view that it was not necessary that all witnesses described the same visit by Gatete and corroborated each other in this respect for the Trial Chamber to find that Gatete had come to the parish prior to 11 April 1994. That the witnesses may have described different visits does not undermine the conclusion that their accounts were compatible on the fact that Gatete was seen at the parish before 11 April 1994.

205. […T]he Appeals Chamber recalls that two prima facie credible testimonies need not be identical in all aspects or describe the same fact in the same way in order to be corroborative.Every witness presents what he has seen from his own point of view at the time of the events, or according to how he understood the events recounted by others. It follows that corroboration may exist even when some details differ between testimonies, provided that no credible testimony describes the facts in question in a way which is not compatible with the description given in another credible testimony.

154.    […] [T]he Appeals Chamber concurs with the opinion of ICTY Appeals Chamber that the testimony of a witness on a material fact may be accepted as evidence without the need for corroboration.[1]

[…]

322.    The Appeals Chamber reiterates[2] that accepting as evidence the uncorroborated testimony of a witness does not in itself constitute an error.[3]

See also para. 187.

449. The Appeals Chamber recalls that under Article 21(4)(e) of the ICTY Statute an accused has the right to examine, or have examined, the witnesses against him. In relation to challenges to a trial chamber’s reliance on evidence admitted pursuant to Rule 92 bis of the ICTY Rules when the defendants did not have an opportunity to cross-examine the witness, the Appeals Chamber of the ICTY stated:

[A] conviction may not rest solely, or in a decisive manner, on the evidence of a witness whom the accused has had no opportunity to examine or to have examined either during the investigation or at trial. This principle applies “to any fact which is indispensable for a conviction”, meaning “the findings that a trier of fact has to reach beyond reasonable doubt”. It is considered to “run counter to the principles of fairness […] to allow a conviction based on evidence of this kind without sufficient corroboration”.[1]

The Appeals Chamber adopts this statement of the law.

[…]

458. […] The Appeals Chamber recalls that the principle that no conviction can rest solely or decisively on untested evidence without sufficient corroboration stems from the fundamental right of the accused to examine, or have examined, the witnesses against him, which is enshrined in Article 21(4)(e) of the ICTY Statute.[2] As Karadžić alleges a violation of his fair trial rights, he must demonstrate that such a violation occurred and show that it caused prejudice amounting to an error of law invalidating the trial judgement.[3]

See also paras. 460 to 473.

474. […] [T]he Appeals Chamber finds, Judges Joensen and de Prada dissenting, that Karadžić has established that the Trial Chamber violated his fundamental right to examine, or have examined, the witnesses against him under Article 21(4)(e) of the ICTY Statute by convicting him after having impermissibly relied solely or decisively on untested evidence in reaching findings in relation to Scheduled Incidents C.27.5, B.20.4, and E.11.1 as well as Scheduled Incident B.13.1 with respect to the killing of one detainee in Kula prison and Scheduled Incident C.22.5 in relation to the mistreatment of two Muslim men at the Magarice military facility. The Appeals Chamber finds that such violations prevented Karadžić from testing evidence related to these specific events which the Trial Chamber relied upon in convicting him. This has resulted in material prejudice invalidating the judgement to the extent that his convictions are based upon these findings. The Appeals Chamber, Judges Joensen and de Prada dissenting, considers that the only appropriate remedy is to set aside, in part, Karadžić’s convictions to the extent they rely on these findings. The impact, if any, such errors may have had on Karadžić’s sentence will be evaluated below.

See also paras. 475, 776, 777.