Forced labor is not exclusive to private prisons. Federal and many state prisons force inmates to work for little or no compensation as well.
Today, more than 76 percent of incarcerated workers surveyed by the Bureau of Justice Statistics say that they are required to work or face additional punishment such as solitary confinement, denial of opportunities to reduce their sentence, and loss of family visitation. They have no right to choose what type of work they do and are subject to arbitrary, discriminatory, and punitive decisions by the prison administrators who select their work assignments.
Forced labor is not exclusive to private prisons. Federal and many state prisons force inmates to work for little or no compensation as well.
https://www.aclu.org/news/human-rights/captive-labor-exploitation-of-incarcerated-workers