Nothing could underscore more the scale of the ethical sourcing challenge facing supermarkets in today’s price-driven market than Panorama’s investigation into the Bangladeshi garment trade. In Dying for a Bargain (BBC1, 8.30pm, 23 September), reporter Richard Bilton exposed the inhumane hours workers are subjected to - and the flagrant lies told by factory managers.

Ha Meem Sportswear, which was making kids’ clothes for Lidl, said workers had left at 5.30pm on a day Bilton had secretly filmed them staggering out exhausted at about 2.30am after a 19.5-hour shift (during which they’d earned little more than £2). Worse, they’d been locked in for part of that time so could have been trapped had there been a fire - the fate that befell workers caught in the Tazreen factory last November.

It was depressing to see how little progress there has been since the collapse of Rana Plaza in April, which killed more than 1,100. Lidl, which described the findings as “concerning”, has now launched an investigation.

But while it’s hard to sympathise with the supermarkets given the factories’ claims that buyers put price before safety, you can appreciate their predicament when their codes of conduct are being so brazenly flouted.

Much as we might want to return to the days when our clothes were made in Britain, it’s not the answer. What retailers can do is open their eyes more fully to the problem - as the plight of these workers demonstrated, there’s still far too high a human price being paid for our cheap clothes.