But this outcome, too, had a steep downside: because it caused returns to capital to increase relative to returns to labor, it benefited capital owners at the expense of low-skilled wage earners.

Colorado recently voted to change the language in its state constitution, so that it no longer allows “slavery” as a form of punishment. And yet prisoners in the state are producing furniture for the University of Colorado for $2.45 per day. What are they, if not slaves?