The dispute settlement mechanism of the World Trade Organization tends to give verdicts for the plaintiff much more often than verdicts for the defendant. Simple logic suggests that this is a puzzle: it is not immediately obvious why defendants do not settle out of court if they are likely to be found guilty. I argue that there are three alternative explanations for this puzzle: imperfect enforcement, asymmetric information, and domestic constraints. By examining three major WTO cases, I find the domestic constraints explanation the most persuasive.