In March 1793, the military situation, political uncertainty, and the rise of domestic tensions led to the adoption of exceptional measures. The historiography, which has traditionally stressed the application and consequencesof these measures, has left largely unexamined the very formulation of these laws. A study of the preparatory work for the law of 28 March 1793 concerning emigres constitutes an important point of departure for exploring the different approaches to law during the Revolution. This legislative work, which took place at a time when laws of exception were introduced, allows us to understand more fully the operation of Comité de législation, a veritable laboratory of law under the Convention.