Britain's new Supreme Court was not "thought up on the back of a fag packet", the former Cabinet Secretary assures me. Lord Turnbull, who was the country's most senior civil servant from 2002 to 2005, rejects widespread criticism that the government had not considered the implications of its announcement six years ago that the House of Lords would no longer be the UK's final court of appeal.
The way the announcement was made, on the back of a government reshuffle, still rankles with the judges. "The major constitutional changes which affected the judiciary in June 2003 were proclaimed without so much as the courtesy of a letter or even a telephone call to the Lord Chief Justice," the present holder of that office, Lord Judge, recalled in July. He remarked, pointedly, that the Statute of Proclamations had been repealed in 1547.
These reforms had been discussed for decades, Turnbull insists. But still the notion persists that the Supreme Court, whose judges will be sworn in on 1 October, was created almost by accident. Would Downing Street have announced on 12 June 2003 that it was abolishing the law lords and the post of Lord Chancellor if Tony Blair had not needed an excuse to sack the then incumbent, Lord Irvine?
Speaking to me for a BBC Radio 4 documentary on the creation of the Supreme Court, Turnbull insists that "quite a lot" of preparatory work had been done in the Lord Chancellor's own department. But Sir Hayden Phillips, the department's Permanent Secretary at the time, tells me he was "slightly taken by surprise in 2003 at the decided firmness of the plans".
Phillips was certainly aware, a few days before 12 June, that reforms were likely. And he knew, of course, that Irvine was opposed to them. But the former civil servant declines to comment on whether he knew in advance that the reforms would definitely be going ahead and that Irvine would be going into retirement.
That seems to be because the decision was not taken until a few hours before it was announced. The former Home Secretary David Blunkett tells me that the Cabinet was not told on the morning of 12 June that Irvine would not be returning. "We didn't even have a chance to thank him for the undoubted contribution that he made."