Ponsonby Rule

The Ponsonby Rule was a constitutional convention in the United Kingdom constitutional law that dictated that most international treaties had to be laid before Parliament 21 days before ratification.

On 11 November 2010 Part 2 of the Constitutional Reform and Governance Act 2010 was brought into force by a commencement order. Part 2 of the Act deals with the ratification of treaties and puts Parliamentary scrutiny of treaties on a statutory footing, so changing the convention into a provision having legal force.

From the late 19th century it became the common practice to present the treaties of the United Kingdom to Parliament after they had come into force.

On 1 April 1924, during the Second Reading Debate on the Treaty of Peace (Turkey) Bill, Mr Arthur Ponsonby (Parliamentary Under-Secretary of State for Foreign Affairs in Ramsay MacDonald's first Labour Government) made the following statement:

It is the intention of His Majesty's Government to lay on the table of both Houses of Parliament every treaty, when signed, for a period of 21 days, after which the treaty will be ratified and published and circulated in the Treaty Series. In the case of important treaties, the Government will, of course, take an opportunity of submitting them to the House for discussion within this period. But, as the Government cannot take upon itself to decide what may be considered important or unimportant, if there is a formal demand for discussion forwarded through the usual channels from the Opposition or any other party, time will be found for the discussion of the Treaty in question.

At the same time he stated that:

Resolutions expressing Parliamentary approval of every Treaty before ratification would be a very cumbersome form of procedure and would burden the House with a lot of unnecessary business. The absence of disapproval may be accepted as sanction, and publicity and opportunity for discussion and criticism are the really material and valuable elements which henceforth will be introduced.

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