This article examines the deposition of the Ottoman governor of Egypt by Cairo’s soldiers in 1676, and a subsequent court case, in order to illustrate the increasing importance of law and legal institutions in Ottoman politics during the seventeenth century. I show that in the court case, the soldiers sought to constrain the actions of future Ottoman governors by establishing legal limits on their authority. I argue that the soldiers displayed a constitutional sensibility: a belief that the conduct of government was bound by rules, and that courts were the place to establish and enforce these rules. This allows us to see the frequent rebellions in the seventeenth- century Ottoman Empire in a new light: as part of an emerging concept of the rule of law that was central to the empire’s transformation from a patrimonial monarchy into an early modern bureaucratic state.