International criminal courts carry out some of the most important work that a legal system can conduct: prosecuting those who have visited death and destruction on millions. Despite the significance of their work--or perhaps because of it--international courts face tremendous challenges. Chief among them is accurate fact-finding. With alarming regularity, international criminal trials feature inconsistent, vague, and sometimes false testimony that renders judges unable to assess with any measure of certainty who did what to whom in the context of a mass atrocity. This Article provides the first-ever empirical study quantifying fact-finding in an international criminal court. The study shines a spotlight both on the testimonial deficiencies that impede accurate fact-finding and on the judges' assessments of deficient witness testimony. Although my previous work on fact-finding has been generally critical of international criminal courts, this large-scale empirical study provides far more reason for optimism This study reveals a host of interesting and sometimes unexpected findings. Taken as a whole, however, it depicts a criminal justice system that labors in the face of severe fact-finding challenges but that has, over the years, appropriately altered its fact-finding practices to respond to those challenges.