Recent studies have highlighted instances where findings of fact reached by international criminal tribunals appear not to be adequately supported by the evidence. These works have typically focused on evidential issues, such as witnesses’ fading memories, cultural differences, and more sinister aspects (such as financial incentives) as the root causes for such discrepancies. However, this article argues that these accounts are incomplete, as they do not recognise difficulties arising from the judicial evaluation of, and reasoning on, the evidential record, which poses potentially insurmountable challenges to reliable fact-finding by international criminal tribunals. This article highlights recent differences of opinion between judges on how evidence should be weighed and evaluated. It points to some issues arising from the enormity of the fact-finding role in international criminal trials and the procedural framework embraced by the international criminal tribunals. It discusses tools to assist fact-finding, and their potential applicability to international criminal trials.