Yup. Quoting Wikipedia: "The 13th Amendment to the U.S. Constitution prohibits slavery and involuntary servitude except as a punishment for a crime where the individual has been convicted"
Mandatory "Penal labour" isn't chattel slavery but it would still be recognised as slavery in any modern understanding.
Mandatory "Penal labour" isn't chattel slavery but it would still be recognised as slavery in any modern understanding.