Can international judges be relied upon to resolve disputes impartially? If not, what are the sources of their biases? Answers to these questions are critically important for the functioning of an emerging international judiciary, yet we know remarkably little about international judicial behavior. An analysis of a new dataset of dissents in the European Court of Human Rights (ECtHR) yields a mixed set of answers. On the bright side, there is no evidence that judges systematically employ cultural or geopolitical biases in their rulings. There is some evidence that career insecurities make judges more likely to favor their national government when it is a party to a dispute. Most strongly, the evidence suggests that international judges are policy seekers. Judges vary in their inclination to defer to member states in the implementation of human rights. Moreover, judges from former socialist countries are more likely to find violations against their own government and against other former socialist governments, suggesting that they are motivated by rectifying a particular set of injustices. I conclude that the overall picture is mostly positive for the possibility of impartial review of government behavior by judges on an international court. Like judges on domestic review courts, ECtHR judges are politically motivated actors in the sense that they have policy preferences on how to best apply abstract human rights in concrete cases, not in the sense that they are using their judicial power to settle geopolitical scores