In answer to questions in the House of Commons on 17 November 1966, the then Prime Minister, the right hon. Harold Wilson MP, said that he had given instructions that there was to be no tapping of the telephones of Members of Parliament and that if there were a development which required a change of policy he would at such a moment as was compatible with the security of the country make a statement in the House about it. This approach, known as the Wilson Doctrine, has been maintained under successive administrations.The Regulation of Investigatory Powers Act 2000 updated existing laws and set in place new legal procedures governing the interception of communications carried on both public and private telecommunications systems. I advised the House in a Written Ministerial Statement on 15 December 2005, Official Report, column 173WS, that I had received advice from the Interception of Communications Commissioner, the right hon. Sir Swinton Thomas, on his view of the implications for the Wilson Doctrine of the regulatory framework established under that Act.It was Sir Swinton's advice, taking into account the new and robust regulatory framework governing interception and the changed circumstances since 1966, that the Wilson Doctrine should not be sustained.I have considered Sir Swinton's advice very seriously, together with concerns expressed in this House in response to my written ministerial statement on 15 December. I have decided that the Wilson Doctrine should be maintained.

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