Baron Neill of Bladen of Briantspuddle in Dorset, 72, has the kind of background which gives him the confidence to put the Prime Minister right on his first day in a new job.
His reputation as "sleazebuster", reinforced this week in a tough report on political party funding, was forged last November, a day into his job as chairman of the committee on standards in public life.
He told Tony Blair to give Formula One chief executive Bernie Ecclestone's donation to the Labour Party back to him, before knowing it was as much as Pounds 1 million.
Son of the late Sir Thomas Neill, JP and younger brother of Sir Brian Neill, former Lord Justice of Appeal, he was warden of All Souls College, Oxford, for 14 years. During that time he also served for periods as vice-chancellor of Oxford University, chairman of the Press Council, head of the inquiry into regulation at Lloyd's of London, chairman of the council for the securities industry and as a director of Times Newspaper Holdings.
Father of six children with his wife Caroline, who is a member of another legal family, the Debenhams, and distant descendant of Joseph Chamberlain, he has been described as a "wise old bird" and "a man with bottom".
Baron Neill was a prime mover in making the Oxford and Cambridge Club admit women. He also allowed women to become fellows of All Souls.
He went to Highgate School, served as a captain in the rifle brigade during the war and later went to Magdalen College, Oxford, where he took a first. He became a Prize Fellow of All Souls by examination, maintaining links with All Souls while practising at the bar and taking silk in 1966.
Baron Neill is opposed to European Union. He was angered by Oxford dons' failure to grant Margaret Thatcher an honorary doctorate.
A regular church attender, he is also interested in forestry and is a keen piano-player.