This is a preprint of Chapter 9 in The Palgrave Handbook of Modern Slavery.
This chapter is divided into two parts. Part I reviews the historical and modern arguments that forms of slavery or servitude should be legally allowed if based on consent (assuming it was genuine). The analogous arguments are also reviewed for the acceptability of non-democratic or autocratic government if based on the “consent of the governed.” Part II examines the counterargument based on the theory of inalienable rights. The basic ideas were anticipated in antiquity and developed from the sixteenth to the nineteenth centuries. The inalienable rights argument is then restated without philosophical jargon in modern terms. To further cement the argument, the basis for abolishing the consensual coverture marriage contract in democratic countries is spelled out as an example. The overall conclusion is that any institution or practice—human trafficking is a modern case in point—that, in effect, treats a person as a non-person, as only a means instead of as an end-in-themselves, violates their inalienable rights and is illegitimate, even with consent.