This is an interesting and complex niche area of the labour market, and one of those things where you instinctively wonder whether or not legislating is actually going to generate net benefit. The Sutton Trust argue that unpaid internships effectively bar young working-class candidates from certain labour markets - notably in the media, financial services and political think-tanks.

However, despite the claims that the Chair of the Sutton Trust thinks that banning unpaid internships of longer than 4 weeks is "a no-brainer and should be implemented without delay”, I'd disagree. There are so many obvious ways around this - rolling internships, token payments to interns and that's before you consider the opportunity cost of policing and monitoring it. And even if you were to ban such things, I don't think it would have a marked effect on social mobility; people with better connections are always going to be able to access certain jobs on preferential terms - the City of London is a classic example.