Treaty scrutiny under the Constitutional Reform and Governance Act 2010

Parliament's statutory role in scrutinising treaties is set out in Part 2 of the Constitutional Reform and Governance Act 2010 (CRAG). CRAG codified into statue a convention established in 1924, known as the Ponsonby rule. The Government must lay treaties before Parliament for 21 sitting days prior to ratification and provide an explanatory memorandum (EM) alongside it (Constitutional Reform and Governance Act 2010, section 20). The progress of all treaties laid before Parliament can be followed on the Parliament's Treaty Tracker.

Parliamentary committees are the key bodies scrutinising treaties. Since November 2000, the Foreign and Commonwealth Office (FCO) has been expected to send a copy of each treaty laid before Parliament to the departmental select committee that it considers relevant. The committee can then decide whether to scrutinise the treaty, and publish a report, or it can pass the treaty on to another committee or committees. If it scrutinises a treaty, it can draw it to the special attention of the House or report it for information.

In the Lords, the Secondary Legislation Scrutiny Committee has carried out CRAG scrutiny since the 2014-15 session as part of its remit to scrutinise “every instrument (whether or not a statutory instrument) ... upon which proceedings may be, or might have been, taken in either House of Parliament under an Act of Parliament” (Written evidence PST0015).

The Lords EU Committee was tasked with scrutinising Brexit-related treaties under CRAG in January 2019. In April 2020, a Sub-Committee dedicated to this scrutiny was formed. The treaties scrutinised were agreements the UK decided to enter in its own name to replace existing EU arrangements after Brexit. The majority were 'roll over' agreements, which were intended to replace agreements previously concluded between the EU and third countries or international organisations. A much smaller portion were new agreements, designed to deal with the consequences of Brexit.

After the end of the post-Brexit Transition Period, a standalone International Agreements Committee was established to continue the scrutiny of treaties under CRAG, and to scrutinise the negotiations of new agreements.

Under CRAG, the House of Commons has the power to delay ratification, while the House of Lords has only advisory power. If the Commons passes a resolution that the treaty should not be ratified, a further 21 sitting day period is triggered which would prevent the Government from proceeding. It can repeatedly pass further resolutions, postponing ratification indefinitely. In 'exceptional cases', a minister may ratify a treaty without going through this process but the Government cannot do so once either House has passed a resolution. A limitation of the CRAG scrutiny process, however, is that there is no requirement for making time for debates or votes—although the Government has committed to facilitating debates if requested by the relevant parliamentary committees.

Further information

Treaties scrutinised by the Lords’ Committees and all reports can be accessed through Parliament’s Treaty Tracker.

Enhanced scrutiny commitments were made by the Government during the passage of the Trade Bill, see: HL Deb, 23 February 2021, col 724 [Lords Chamber]

Lords European Union Committee's explainer on “Brexit-related treaties”

European Union Committee, Scrutiny of international agreements: lessons learned (42nd Report, Session 2017-19, HL Paper 387)

Constitution Committee, Parliamentary Scrutiny of Treaties, (20th Report, Session 2017-19, HL Paper 345)

Written evidence from the Secondary Legislation Scrutiny Committee PST0015, cited in the Constitution Committee's Parliamentary Scrutiny of Treaties report

A Lang, Parliament and International Treaties, in A Horne and A Le Sueur (eds) Parliament: Legislation and Accountability (Hart/Bloomsbury 2016) pp 241-264