A foundational dichotomy in Public Law is that of Rule of Law and Rule by Law, sometimes marking a distinction between liberal-democratic and authoritarian States. Against such essentialism, this paper argues that within a given State, the constitutional order is characterized by coexisting layers of liberal-democratic and authoritarian norms. This constitutional dualism is structured along a multidimensional axis. The Constitution grants or denies protection depending on the individual, the subject-matter, the time, and the place. These fault-lines fluctuate according to the workings of reason of State and the practice of sovereignty. Based on a critical reading of French constitutional history from the French Revolution until the Yellow-Vests Movement, this paper documents the operation of dual constitutionalism in the French context. It suggests that Rule of Law and Rule by Law are two sides of the same coin – constitutionalism being a process of both inclusion and exclusion.