(CNN) Next month, Colorado will vote on changing the language in its state constitution so that it no longer allows slavery as a form of punishment. Slavery is technically -- technically -- still legal in many states.

Wait, slavery is legal?

Article II, Section 26 of Colorado's constitution reads that there "shall never be in this state either slavery or involuntary servitude, except as a punishment for crime, whereof the party shall have been duly convicted." [Emphasis added]

That's what legislators are putting on the ballot this year. Amendment A will change the wording to "There shall never be in this state either slavery or involuntary servitude." [Again, emphasis added.]

Voters almost passed the amendment two years ago. But the wording was so unclear that it confused many people about whether they were voting for or against slavery, said Jumoke Emery with Abolish Slavery Colorado.

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