Lord Turnbull, who was Cabinet secretary in the run up to the Iraq war, told the Chilcot Inquiry into the war that there were important differences between the final legal opinion Lord Goldsmith (the then Attorney General) presented to the Cabinet and an earlier version he gave privately to Tony Blair.
"It was not, in my view, a summary of what had been produced 10 days earlier. It was materially different in some respects because of the passage of time.
Certain things had changed."
Why such large changes over such a short period of time?