"Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States or any place subject to their jurisdiction." U.S. Const. amend. XIII.
It is a violation to coerce someone "by improper or wrongful conduct" into service by causing and intending to cause him "to believe that he . . . has no alternative but to perform the labor." Brogan v. San Mateo County, 901 F.2d 762, 764 (9th Cir. 1990)(citation omitted). The fact that someone must perform certain duties as a condition of his employment, does not violate the Thirteenth Amendment. Cf. United States v. 30.64 Acres of Land, 795 F.2d 796, 800-01 (9th Cir. 1986) (requiring lawyers to perform pro bono services does not violate Thirteenth Amendment because requirement is a condition of practicing law).