International criminal tribunals (ICTs) constitute one of the primary examples of international institutions vested with undisputable international authority. The decisions of ICTs are final, binding on the parties to the proceedings and cannot be overturned politically. Given the proliferation of ICTs and their increased significance in current international politics, it is important to examine how international criminal judges exercise this authority. Is the exercise of such authority biased toward their homeland's political interests? This question is yet to be answered in both international criminal legal research and international relations research. Using non-hierarchical multi-level modelling, we examine the sentencing decision-making of judges at the International Criminal Tribunal for the Former Yugoslavia (ICTY). Our analysis indicates that judges act as independent actors, and are not biased in the exercise of their authority.