The prosecution at the Old Bailey confined itself to trying to prove Berkowitz's guilt on either a charge of burglary or of handling stolen goods. It said the police had been unable to answer the 'intriguing' and wider question: had the thief broken in because he knew that evidence of Mr Ashdown's affair with Patricia Howard, his former secretary, was lying in a safe in the basement of the City of London firm?
David Bate, for the prosecution, told the court that only Berkowitz was in a position to reveal what had happened. But he was pleading not guilty and keeping quiet. All Berkowitz, a professional criminal and vocal Tory supporter, would admit was that he passed on a copy of the document to a News of the World reporter, a few days after the raid on Bates, Wells and Braithwaite in the second weekend of January. His act eventually forced Mr Ashdown to admit the affair.
Conspiracy theories have been fuelled because of the peculiar nature of the burglary and the fact that it coincided with other allegations that there were plots against Mr Ashdown in the run- up to the general election.
The break-in left staff at the firm puzzled. Keys to safes and locked doors had been left either in or on the desks of administrative staff so the burglar had the run of the building. But all he took was the Ashdown memorandum and pounds 223 in petty cash.
Joyce Drakeley, the office manager, said the building looked so neat when she arrived at work on the Monday after the burglary, she got the impression that 'someone who knew what he was looking for' had been there.
Mr Ashdown's solicitor, Andrew Phillips, rejected the idea that he could have been the victim of a planned theft. He said that only he and his secretary, whom he trusted implicitly, knew that notes of a consultation with Mr Ashdown about the affair on 31 May 1990, had been typed up.
The sole record of the document was in a notebook kept by his secretary. The aide memoire's existence had been pushed so far back in his mind that he did not order a search for it until he got wind, on 29 January, of the News of the World inquiries. 'I'm convinced the theft was a fluke,' he said outside the court. 'Even if someone knew of this document's existence, the chances against him finding it were enormous.'
But Mr Phillips's faith in the cock-up theory of history has been shaken by two 'very fishy' further break-ins - one on 7 February and one during the election campaign. On both occasions someone went through his papers but took nothing.
At the time of the second and third break-ins, there were rumours of smear attempts. The Independent was told by a Conservative MP that he had been assured by senior colleagues that support for Labour and the Liberal Democrats could be diminished by scandals which would break during the campaign.
Meanwhile Kelvin MacKenzie, editor of the Sun, has revealed that in the second week of the campaign a Cabinet minister called his office with false allegations. He offered 'the names and telephone numbers of five women that Paddy Ashdown, he alleged, had some association with,' Mr MacKenzie said. 'Totally untrue, by the way.'