Is the television watershed still relevant after 50 years?

The television watershed, enforced by Ofcom to ensure content unsuitable for children is not broadcast before 9 o'clock in the evening, is 50 years old.

Stewart Purvis, professor of television journalism at City University, told the Today programme that politicians are consistently looking to extend the protection it provides children to digital media.

Broadcast on BBC Radio 4's Today programme on Thursday 3 July.