The eco guide to prison labour

The world's biggest companies, from Starbucks to Victoria's Secret, use prisoners to work on their products. Is it helpful work experience or sheer exploitation?

We are all, at heart, ethical consumers. I've never met anyone actively looking for a dose of slave labour with their teabags, window frames or underwear.

71% of companies surveyed in 2015 believed their supply chains might contain some form of slavery