In 2003, when Head of News at the BBC he was asked to head up a landmark workstream looking at the BBC's Values. As Head of Sport he cancelled "Grandstand" after a 48-year run and oversaw the move to Salford Quays in 2010. He was in charge of the BBC's coverage of the 2012 Olympics, and was replaced as Head of Sport by Barbara Slater, who oversaw the move of BBC Sport to MediaCityUK in Salford Quays in 2011. He became the BBC's Editorial Director in May 2013, but this appointment proved to be short lived. Upon leaving the BBC, Mosey highlighted the various biases in the work of the organisation. Writing in The Times, he noted that the organisation was too left-wing, had failed to "give enough space to anti-immigration views or to EU-withdrawalists" and had uniformity in its views. Mosey proposed that the organisation should share the licence fee with others.