What role did slavery play in the southern plantation economy? how was it regulated?

The role that slavery played in the southern plantation was valuable for the plantation owners but deeply abhorrent. Slavery was of course free labor for these Southern plantations. Due to the fact that the children of slaves were born into slavery themselves, it was also a reliable source of labor. The use of free labor meant far more profits for the owner, who was already protected due to special laws. For example, the runaway slave law meant that if a runaway slave was found by any member of the public, they would have to be returned to their owner, even if caught in a state where slavery had already been abolished.

Is there a picture that goes with this question?