 They established white supremacist regimes of Jim Crow segregation in the South and one-party block voting behind southern Democrats.The Democratic whites denied African Americans their exercise of civil and political rights by terrorizing black communities with lynch mobs and other forms of vigilante violence as well as by instituting a convict labor system that forced many thousands of African Americans back into unpaid labor in mines, on plantations, and on public works projects such as roads and levees.Convict laborers were typically subject to brutal forms of corporal punishment, overwork, and disease from unsanitary conditions.