The opinions were sought by Sir Nicholas some time before the arms-for-Iraq trial in 1992. They were later incorporated into guidance circulated, after five earlier drafts, to all Whitehall lawyers.
The provenance of the opinions from John Ainley QC, Michael Kallisher QC and John (now Mr Justice) Laws, formerly First Junior Treasury Counsel, has helped to convince Sir Nicholas that he has a watertight legal case to present when he fights for his political life before the Scott inquiry today.
In an unprecedented development last night, Sir Nicholas appeared intent on securing positive advance publicity, agreeing to televised interviews with the BBC and ITN. He told ITN he had considered resigning after the trial collapsed, and had rejected the idea.
But Sir Nicholas's defence coincides with growing acceptance in Whitehall that use of the PII system to keep official information secret has become too automatic. There is also recognition that Alan Moses QC, the leading prosecutor in the trial, was shown some documents the Government wanted kept secret, at too late a stage.
The Attorney General's position appeared to be seriously undermined by Mr Moses' evidence to the inquiry this week that an assurance from Sir Nicholas to Michael Heseltine over his concerns about signing a certificate was not passed on to the court.
Cabinet colleagues have not been conspicuous in rallying round him.
Sir Nicholas, however, is determined not to be forced from office as the sole scapegoat for the storm that broke after the prosecution for evading export controls collapsed with the 'economical with the actualite' evidence of a former defence minister, Alan Clark. His unwillingness to become a fall-guy could mean the critical spotlight being retrained on earlier players.
Five ministers signed immunity certificates which sought to withhold classes of Whitehall documents from the defence, but only Mr Heseltine contacted Sir Nicholas to protest over the form of his certificate, drawn up by the Department of Trade
The questions facing Lyell, page 3
Leading article, page 19
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