Lighten, a Dutchman, had tried to join MI5 and was viewed with suspicion by the intelligence services as possibly a German agent. Liversidge himself provided secrets to the War Office. In the Second World War Liversidge volunteered for the army at the time of the Munich Agreement in September 1938 and for the Royal Air Force Volunteer Reserve in September 1939, using the false date and place of birth that he had used when obtaining his Canadian passport. He was commissioned Pilot Officer on 26 November 1939, and served as an intelligence officer in Bomber Command at RAF Wyton and RAF Wattisham, then in Fighter Command at RAF Biggin Hill and RAF Bentley Priory. Defence Regulation 18B, which had been imposed at the start of the war, authorised internment. In early 1940 MI5 received intelligence that "three notorious Jew swindlers" were using "improper pressures brought to bear in High Places" to effect the release of internees from a camp at Seaton, Devon in return for payment of £500 (about £17,700 at 2003 prices). Thwaites was implicated, Liversidge was investigated, and the falsehoods about his birth were revealed. Liversidge was arrested on 26 April and charged with making a false statement. His flat was searched and the names of other persons known to the intelligence services were discovered. When he was interviewed it came to light that Liversidge had previously been Jack Perlsweig. Allegations There seems to have been no evidence that Liversidge had "hostile associations" or had committed "acts prejudicial" to public safety. However, on 15 May the Secretary of State for Air, Sir Archibald Sinclair, wrote to the Home Office recommending that Liversidge be interned because "I am certain that you will agree that it is most undesirable that a man with the unsavoury and indeed dangerous associations of Perlsweig, who during recent months has had access to information of a most secret character, should be left at large either in the Service or in the Country." The Reasons for Order served on Liversidge on 2 October alleged "hostile associations" only in count 7: Liversidge's lawyers demanded particulars of these associations, but were refused. The more detailed Statement of Case asserted that Liversidge had "a very bad record," and referred to the Baumgart case and the Canadian passport application. It then alleged, on the word of the informant from 1937, that Liversidge had used the alias "John Stone" and