AN important new witness was heard yesterday in the increasingly heated affair of Downing Street v the BBC. Sir Bernard Ingham who for many years was to Margaret Thatcher what Alastair Campbell is to Tony Blair was asked on BBC radio's Today programme what he thought of Mr Campbell's appearance on Channel 4 TV on Friday night. His answer was typically blunt and to the point: Either he's flipped his lid or he's demob happy. And he's behaving like the obsessive we all know him to be. Sir Bernard said something else that may be very relevant: Alastair Campbell's entire press office regime at No 10 has been built on the bullying of journalists. take this evidence very seriously. I know from many years of working closely with Bernard Ingham that he calls a spade a spade and can be extremely robust in getting what he wants done. He was the most abrasive prime ministerial press secretary since the post was invented in Atlee's government and he could be very frank indeed with the media but no one ever doubted his integrity. When he said in the radio interview that Mr Campbell should not talk about the integrity of the government, as he had done on television, because this government has no integrity it was a damning blow. It would be difficult to overstate the importance of the standoff between Downing Street and the BBC. If Mr Campbell had merely said, in measured terms, that he refuted everythng the BBC had said about his role in the preparation of the dossiers and that he had expected better of the BBC, the matter could have rested. But by insisting on an apology and even suggesting that he might make a formal complaint to a regulatory body, he has ensured that the stakes are raised. Meanwhile, and perhaps as Mr Campbell intended, the central issue is being lost sight of. The issue the Select Committee is supposed to be looking at is whether intelligence material about Iraq was properly used in the runup to the war. Of far more compelling interest on this matter than the BBC's contribution was the one made by Robin Cook a few days earlier. He said, very clearly indeed, that in his view Parliament and the public were told things in justification of a war that have proved to be wrong and that intelligence had been used to support an alreadydecided policy rather than to form that policy. As a former Foreign Secretary and Leader of the House of Commons Mr Cook was at the centre of government before his resignation of the eve of the war. His evidence cannot be overlooked by the Committee; it is of infinitely greater importance than the protection of the amour propre of Alastair Campbell. There are two MPs' Select Committees looking at these questions. One is sitting in public, for the most part, and its report will be published. The other sits in private and reports to the Prime Minister who can decide whether or not to publish its report. If these committees do not reach clear conclusions, or if they disagree with one another, and if Mr Campbell pursues his vendetta against the BBC, we may yet find that a full judicial enquiry cannot be avoided.