John Rentoul is The Independent’s chief political commentator, having worked for the title since 1995. He is also visiting professor at King’s College, London, and a prominent tweeter. He is the author of a biography of Tony Blair and, with Jon Davis, of Heroes or Villains? The Blair Government Reconsidered. As well as writing about politics, he contributes a weekly top 10 of curiosities and Mea Culpa, a column about style and usage