It was disclosed by the government yesterday that he had given the go-ahead in 1996 for the revelations of the KGB defector, Vasili Mitrokhin, to be put into the public domain. Among those papers was the crucial information about Mrs Norwood, the KGB spy known as Hola.
Sir Malcolm's role at least is relatively clear. Little else is. In the world of spies, confusion is preferable to clarity. When this is overlaid by in-fighting between the present Labour administration and the previous Tory one, truth can be hard to come by.
The shadow home secretary, Ann Widdecombe, wants the government to be blamed for not prosecuting Mrs Norwood. Labour does not want to find itself in the kind of spy affair that has unsettled governments since Macmillan.
So who knew what? Mitrokhin, the KGB archivist with access to lots of Soviet secrets, defected to Britain in 1992. It was a big coup for MI6, which is responsible for intelligence-gathering abroad, and it was quick to let the then Tory government know about it.
One minister at the time, while saying his memory is not exact, believes he was told about the coup but not about the details of what Mitrokhin brought with him.
The intelligence services spent the following four years assessing the material. Mitrokhin brought no documents with him, just scribbled notes, including information about Mrs Norwood. The security services had been suspicous about Mrs Norwood, who worked for the British Non-Ferrous Metals Research Association, since the 1940s. She was given security clearance in 1945 but this was revoked six years later. The security services conducted another investigation into her in 1965 without success. The then Labour home secretary, Sir Frank Soskice, was informed.
According to the security services, they did not act on Mitrokhin's information about Norwood almost 30 years later because they were following up other leads and did not want these blown. One intelligence source suggested yesterday she was regarded as small beer.
When the intelligence agencies went to Sir Malcolm four years after Mitrokhin's defection, the foreign secretary was asked to approve publication by making it available to Christopher Andrew of Cambridge university - whose book will be published this week.
Sir Malcolm, who was asked yesterday by Mr Straw if his role could be made public, said last night that his understanding was that the notes referred to broad Soviet policy, not information about British citizens such as Mrs Norwood. He insisted he knew nothing about Mrs Norwood.
The puzzle remained last night as to whether other Tory ministers, such as the home secretary, Michael Howard, or the attorney-general, Sir Nicholas Lyell, had been informed about Mrs Norwood. If not, why not? Sir Nicholas insisted yesterday he had not been told.
But how does this square with the reported creation of a cross-departmental committee that year to deal with the Mitrokhin allegations. That included not only the foreign office but the home office and the attorney-general's office.
When Labour came to power in 1997, MI6 briefed the new foreign secretary, Robin Cook, and asked him about the timing of publication of Professor Andrew's book because it could have implications for British-Russian relations.
But the foreign office is adamant that Mr Cook was not told about Mrs Norwood: prosecution of British citizens is not part of his departmental brief. That is a matter for the attorney-general and the home office.
The home secretary, Jack Straw, was similarly briefed by the security services when he took over in 1997 about the book but not about Mrs Norwood. He said yesterday: "I was first made aware of the role of Mrs Norwood in a minute in December 1998 which informed me of the plans to publish the book."
The attorney general, John Morris, informed the home office last spring that prosecution of Mrs Norwood was "inappropriate".
Last month, Mr Straw was informed that the security services were seeking advice on whether Mrs Norwood's alleged confession to the BBC could be used against her. Home office sources said yesterday that the case could be reopened as a result of the interview, but it was highly unlikely.
As for Tony Blair, he was among the last in the know, according to Downing Street. His spokesman said he was told late on Thursday, just ahead of publication of excerpts from Professor Andrew's book in the Times.
