Desire not to upset the Royal Family may be behind the British government's continued refusal to release key documents relating to the Profumo affair of 1963, according to a leading British historian.
The affair led to the resignation of a minister, John Profumo, the Secretary of State for War, after he lied in response to claims that he had compromised national security by having a relationship with a prostitute also known to a Soviet military attaché.
Richard Davenport-Hines, author of An English Affair, published last year, said he believes unfounded allegations made against the Duke of Edinburgh at the time of the scandal may continue to give rise to jitteriness in high places.
Last week, it was confirmed that the papers, mostly of interviews with around 160 witnesses, will not be destroyed, as some had feared, but will remain under lock and key for up to a further 50 years.
Speaking in the House of Lords last year, Lord Wallace of Saltaire, the Lords spokesman for the Cabinet Office, said there were "some sensational personal items" in the files, although he does not know what they are.
He added: "At the time, Lord Denning [who conducted the Government's inquiry into the affair] refused to allow the head of the Security Services access to the papers." A very senior civil servant who has seen the papers is known to have also used the word "sensational" to describe them.
Emphasising that he is "only guessing", Davenport-Hines told The IoS that he believes it was significant that the Prince Philip had been sketched by Stephen Ward, the society osteopath at the centre of the story.
"In June of 1963 the Daily Mirror, in order to get a juicy headline, accused the Duke of involvement with Christine Keeler and others. In fact, and I am very emphatic about this, the duke had no such involvement, but I imagine Denning would have interviewed courtiers and others about the duke, and that suspicion would be enough to embarrass the Royal Family."
The headline in question, "Prince Philip and the Profumo scandal – rumour utterly unfounded" was, writes Davenport-Hines in his book, part of "the raucous period when authority figures were denied respect even when they deserved it". An invitation by Denning to members of the Buckingham Palace staff to unburden themselves of any rumours – unchecked and unsourced – they may have heard, substantiated or otherwise, may have encouraged tongues to wag in a manner that did not reflect well on the Prince Philip.
Denning's report was considered by some to have been a whitewash, but he did have extensive access to those involved. Davenport-Hines says the judge was "something of a dirty-minded nosy parker who rather got off on asking prurient questions – he did the same with the Duchess of Argyll over her divorce case, when it had no relevance to the Profumo case. Had he discovered anything, I'm sure he would have sat on it absolutely. He was one of the judges who thought he could hold back and repress and punish all the new sexual freedom that was about at the time."
"The Mirror ran its story because they thought they'd have a good headline. They were terribly keen to damage the Conservative government and crank up the class war, so they wrote stories about how the Tories were having a better time, better sex and so on, than most people. This sort of stuff helped Labour win the 1964 election."
The constitutional expert Lord Hennessy told The Independent on Sunday: "I don't know, and wouldn't want to speculate as to who this relates to, but I suspect it has to do with the sensitivity of surviving family members, whoever they are, royal or otherwise.
"The Denning findings weren't tested in court, so there may be unfounded claims in there. That was the summer of credulity, when anything was believed for a while and every conceivable rumour took on a life of its own. The Cabinet Secretary has what I call the 'too-hot-to-handle' archive, which is off the Richter scale of 'need to know', and the number of people with access to that is tiny. My instinct is we'll have a 100-year wait, until January 2064, when the children are no longer around, before we are told."