Particularly in areas on the western frontier between slave and free states, for instance in St. Louis, Missouri and in Louisiana, hundreds of slaves filed freedom suits, challenging the grounds of their enslavement and sometimes winning freedom. The legal justifications for the institution of slavery included exceptions.
In areas on the western frontier, where slave and free states coexisted, such as St. Louis, Missouri and Louisiana, hundreds of slaves challenged their enslavement in court, with some winning freedom. The laws that allowed slavery acknowledged certain circumstances or exemptions.