Collective Action, White Flight, and the Origins of Formal Segregation Laws

This paper develops and tests a simple model to explain the origins of municipal segregation ordinances. Passed by cities between 1909 and 1917, these ordinances prohibited members of the majority racial group on a given city block from selling or renting property to members of another racial group. Our results suggest that prior to these laws cities had created and sustained residential segregation through private norms and vigilante activity. Only when these private arrangements began to break down during the early 1900s did whites start lobbying municipal governments for segregation ordinances.