Recent scholarship has demonstrated that law and legal institutions were crucial mediators in the relationship between the early modern Ottoman state and its subjects. However, scholars have paid far less attention to the role of law in framing the relationships between the Sultan and the ruling elite that exercised his power. This paper examines the legal consequences of the deposition of the Ottoman governor of Egypt, Defterdar Ahmed Pasha, by the Cairo soldiery in 1675. This incident demonstrates a profound transformation in the relationship between the Ottoman government and the provincial Egyptian elite, which saw law and legal institutions play an increasing prominent role in politics. Defterdar Ahmed Pasha was violently deposed after attempting to implement a package of fiscal and administrative reforms that threatened the interests of the soldiers and notables. Fascinatingly, after deposing the governor by force, a group of soldiers launched a lawsuit in a Cairo shari‘a court that aimed to place limits on the actions of future governors. The hujja issued by the judge at the conclusion of this lawsuit survives at the Basbakanlik Archive in Istanbul; my paper is based on a close reading of this hujja, which I contextualize using accounts of the deposition in a range of contemporary Arabic and Turkish chronicles. I argue that the soldiers who launched this lawsuit displayed a constitutional sensibility, believing that their relationship with the Ottoman government was regulated by law, and that there were rules according to which government should function. I show how the soldiers used an Islamic legal procedure, and an appeal to the authority of custom, to claim for themselves the right to define important aspects of public law: the way that the Ottoman governor should interact with the Egyptian establishment, and the particular officials who should be involved in negotiating policies. I suggest that this incident represents a particular moment during the development of an early modern Ottoman concept of the rule of law.