During the administration of Michel-Étienne Turgot a new rational policy was introduced to renew the bonds between the king and his people. In 1776 Turgot entrusted Albert (Lieutenant of Paris Police) with the task of redrawing the boundaries of the Parisian police districts. The aim was to associate to the municipal government all important persons in the physiocratic system: merchants, shopkeepers, etc. This reform took place within the context of the abolition of corporations and the redefinition of political rules in the city. But all these reforms did not produce a consensus in the population or within the police force, and was especially opposed by the “commissaires”. We pose the question of how the new boundaries were drawn, and what scientific knowledge was used in the process? The opposition that it faced, and its final abandonment, reveal the complexities of creating of a new public urban order.