It’s 157 years since the US constitution banned chattel slavery – in which one person is the legal property of another – but left in place an exemption for convicted prisoners.
Throughout most of the US, slavery is still legal as punishment for a crime.
But on 8 November, voters in five states – Alabama, Louisiana, Oregon, Tennessee and Vermont – will decide whether to remove these exemptions from their state constitutions in an effort to ban slavery entirely.
The outcome could enable prisoners to challenge forced labour. Some 800,000 currently work for pennies, or for nothing at all. Seven states do not pay prison workers any wage for most job assignments.
Supporters of change say it’s an exploitative loophole that must be closed.