> The words involuntary servitude have a "larger meaning than slavery." "It was very well understood that, in the form of apprenticeship for long terms, as it had been practiced in the West India Islands, on the abolition of slavery by the English government, or by reducing the slaves to the condition of serfs attached to the plantation, the purpose of the article might have been evaded if only the word 'slavery' had been used."

If there wasn't a distinction between the two, the Amendment wouldn't need to mention both.

If I see forced unpaid laborers, I'm entirely comfortable deeming them slaves. (They'll probably learn about similar forms of slavery in history class; https://en.wikipedia.org/wiki/Slavery_in_ancient_Rome, for example. In current affairs, https://en.wikipedia.org/wiki/Slavery_in_the_21st_century)