prison labor, again, is only something you can participate in in this country if you've been convicted in a court of law by your peers. many indentured servants were kidnapped and given forged documentation and had no possible recourse because they effectively had no rights to participate in the legal or political systems in any way
sounds like
by law they are very similar, even if it was abused in practice. of course, wrongful convictions and falsified evidence exists, too.
also prisoners are also barred (no pun intended) from voting in particular states (especially Southern states which feed off prison labor) and have no possible recourse.