المحكمة الجنائية الدولية ليوغوسلافيا السابقة
Ball served as an expert witness in testimony at the International Criminal Tribunal for the former Yugoslavia against Slobodan Milosevic, the former President of Serbia. He was also an expert witness for the Prosecution at the International Criminal Tribunal for the former Yugoslavia in Milutinović et al. (IT-05-87).