For the minister in charge of the RAF during the Cold War it seemed the most natural explanation for being photographed in bed with prostitutes while smoking cannabis. He was bored.
Lord Lambton - whose resignation in May 1973, along with a second Tory peer also caught using call girls, shook Edward Heath's government - told an MI5 officer that the "futility" of his job and a battle over his title had driven him to "vigorous activity", namely gardening and membership of a sex ring.
Security Service documents released today show that Lord Lambton, who was feared to have leaked highly sensitive secrets to at least one prostitute, was believed to be on the verge of a nervous breakdown.
The double resignation of Lord Lambton and Lord Jellicoe, who was Lord Privy Seal and Tory leader in the House of Lords, caused panic in MI5 over the possibility that a foreign power, such as the Soviet Union, could have entrapped two senior government ministers with access to vital secrets.
An emergency inquiry by the Security Commission, the parliamentary body set up to investigate potential leaks, later dismissed the notion, praising Lord Jellicoe for the "discretion" with which he conducted his assignations. But a previously unseen report by the unnamed MI5 officer responsible for questioning Lord Lambton, who was embroiled in a dispute over the use of his title as 6th Earl of Durham, gave a startling insight into the peer's attitude towards the Ministry of Defence, where he was under Secretary of State for the Royal Air Force.
Noting that Lord Lambton denied a claim by Norma Levy, the prostitute at the centre of the scandal, that the minister took his official briefcase to her flat, the MI5 officer said: "He had never taken any of his papers out of the office. Indeed, he had no need to since he had so little work to do. He rather implied that the futility of the job was one of the reasons that he had got up to mischief."
The peer's sex life, labelled "debauchery" by the Security Service, came to light after Mrs Levy's husband, Colin, a small-time crook, hid himself in the attic of their home to take explicit photographs and make a recording of the minister talking about his use of drugs.
The documents note that, when Mr Levy then approached the News of the World to sell the story, the paper thought the pictures were of such poor quality that it sent its own team to take more secret shots. By this stage, Lord Lambton was already under MI5 surveillance and when confronted with the evidence he was forced to resign.
The MI5 report said there had been "photographic evidence of sexual practices which deviated from the normal".
A subsequent storm of publicity revealed that Lord Lambton had been a client of an exclusive vice ring. The peer, who drove to Mrs Levy's London flat in his ministerial Rover, said he had used a number of prostitutes, including a "tall German girl", but could not remember details.
The Security Service report continued: "He said that he had, throughout his life, made use of prostitutes from time to time but that his behaviour since July 1972 was out of character and had been caused by his obsession over his failure to win his battle to use his title.
"This had become an obsession with him to such an extent that he was no longer able to read - and had sought to forget his obsession in frantic activity. He had, for example, become an enthusiastic and vigorous gardener. Another example of this frenzied activity was his debauchery."
The officer revealed that such was the extremity of Lord Lambton's conduct that he believed his mental health was at risk. He wrote: "He is on the verge of a mental collapse."
The authorities were prepared to be more forgiving towards Lord Jellicoe, who fell from grace when two informers involved in Lord Lambton's case mentioned his name. A report to Mr Heath said: "There is nothing in his conduct to suggest that the risk of indiscretions on these occasions was other than negligible."
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