Parliamentary Scrutiny of International Agreements in the 21st century – Report Summary

This is a House of Commons Committee report, with recommendations to government. The Government has two months to respond.

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The UK’s constitutional arrangements for reaching international agreements and how they are scrutinised by the UK Parliament has been brought to the fore by the UK’s withdrawal from the European Union. We have found these arrangements to be wanting in terms of the opportunities provided for scrutiny and in the unfettered exercise of the international relations prerogative power, and as a consequence consider the status quo to be constitutionally inappropriate in the 21st century.

International agreements broadly take two forms: legally binding agreements known as ‘treaties’, and agreements that are politically but not legally binding, known as ‘non-legally binding instruments (NLBIs)’. Under the UK’s constitutional arrangements, the power to negotiate and enter into treaties is drawn from the royal prerogative. This means that the power still rests notionally with the sovereign, but in practice is exercised exclusively by the Government, who have considerable power and flexibility in how it is used. In order for the exercise of the prerogative power by the Government to be legitimate, a Minister must assure themselves that they are acting in accordance with the will and confidence of the House of Commons.

The UK is a dualist state, meaning that our domestic law (law that has effect within the state) is separate from international law (law that places obligations on the state at the international level), and so international law obligations must be implemented to have effect in domestic law. At first glance, this appears to provide Parliament with the opportunity to consider treaties during their implementation phase. However, treaties are often implemented either only in part through primary legislation or through secondary legislation. As such it is clear that Parliament’s opportunity to debate, approve or reject implementing legislation is no substitute for proper parliamentary consideration of the entirety of a treaty.

While the UK was an EU Member State, many of the treaties the UK was party to were negotiated and scrutinised at the EU level. Now the UK has left the EU, treaty scrutiny arrangements have reverted to those that emerged and crystallised almost a century ago. It is clear that during the last century there has been significant quantitative and qualitative changes to the nature of international agreements. International agreements now reach into people’s everyday lives in the UK and around the world, with agreements now concerned with domestic as well as international affairs. Accordingly, this makes them an issue of fundamental concern for Parliament and the scrutiny of international agreements one of its core constitutional functions.

Until 2010, Parliament had no statutory role at all in the process of the UK entering into international obligations. Instead, by convention, Parliament was given the opportunity to consider and scrutinise treaties (at least, that is, those that require ratification) for 21-sitting days. The Constitutional Reform and Governance Act 2010 (CRAG) sought to place this convention into statute which, for the first time, provided the House of Commons with a legal tool to delay ratification where it was not satisfied with a treaty. Under CRAG, the Government is required to lay some treaties, along with an explanatory memorandum, and after a period of 21-sitting days, if the Commons has not voted to delay ratification, a treaty can be ratified. The evidence we received was clear that CRAG has been an insufficient legislative tool to facilitate meaningful Parliamentary scrutiny of treaties. We identified three main areas of concern with the current system for parliamentary scrutiny of international agreements under CRAG:

  • the current legislation provides only a passive role for Parliament and as such there is no opportunity for Parliament to express its explicit approval or disapproval of a treaty.
  • several categories of treaty are not captured by CRAG at all.
  • the 21-sitting day period is an arbitrary and, in many cases, wholly insufficient period for the scrutiny of treaties, especially in light of their increasing length, complexity and impact on the domestic level.

In order for the arrangements for entering into treaties to respect the core constitutional principle of Parliamentary sovereignty, Parliament must be given the opportunity to give its express approval to all treaties before they can be ratified or enter into force. We recommend that CRAG be amended to implement new arrangements to give effect to this principle and propose a new system by which the House of Commons must indicate its explicit approval of international agreements for them to bind the UK.

Under the new system, the Government would be required to submit all treaties to a sifting committee, which would have 21-sitting days to recommend either a ‘standard’ scrutiny period of 21-sitting days, or an ‘extended’ scrutiny period which will vary in length depending on the content of the treaty itself. The purpose of the scrutiny period is to allow parliamentary committees, as well as other stakeholders across the UK, to carry out effective scrutiny of the treaty and to inform the debate in the House of Commons to approve the treaty. A treaty would then be brought forward for a debate and approval vote in the House of Commons. Amendments to treaties by contracting parties or bodies established under those treaties, which are currently often not captured under the CRAG arrangements, should also be provided to the sifting committee so that Parliament can consider those which the committee deems to require scrutiny and approval.

The other category of international agreements we examined in this inquiry is non-legally binding instruments (NLBIs). These are political agreements reached between states or other international actors which create no legally binding obligations under international law, but can impose political obligations that guide Government action and can even result in financial obligations being placed on the UK. When the UK makes such commitments, this should be viewed as essentially equivalent to making a legally binding obligation. In our view, Parliament needs to be kept informed of all international agreements, including NLBIs. We therefore call for the establishment of a central repository for all non-binding instruments - to be published on GOV.UK - and for Parliament to be notified of all new or updated documents added to the repository. We also recommend that a convention be established whereby if Parliament raises concern about an NLBI, the Government will make time for a debate on that instrument on the floor of the House.

For Parliament to carry out its constitutional role effectively in regard to the scrutiny of international agreements, it is not enough for it only to be involved at the end. A new approach to thinking about how the UK reaches international agreements, whereby Parliament is involved throughout the treaty process, including a role in setting negotiating mandates and monitoring ongoing negotiations, is required. We recommend that a working practices agreement setting out arrangements for how Parliament will be informed of the progress of negotiations and consulted on negotiating mandates be produced.

While there has been a recognition that Parliament’s role in the scrutiny of international agreements is insufficient for some time, the House of Commons has still not developed satisfactory systematic scrutiny arrangements. The House of Commons’ ability to carry out satisfactory and effective scrutiny was further set back by the abolition of the International Trade Committee in 2023. The departmental committee structure in the House of Commons, however, makes it well placed to carry out detailed policy-focused scrutiny on international agreements. We recommend that the scrutiny of international agreements be added to the core tasks and remit of all relevant committees. Moreover, we recommend that a dedicated treaty scrutiny committee is established to act as the focal point for and to lead on the scrutiny of international agreements in the House of Commons.

While the legal authority and responsibility for international agreements rests with the UK Government, devolved governments and legislatures will necessarily have a legitimate interest where agreements intersect with areas of devolved competence. We found that the current arrangements for timely and meaningful consultation between the UK and devolved governments on the negotiation of international agreements that impact areas of devolved competence are not working effectively, and have thus recommended that they be updated or replaced. Devolved legislatures will also have an interest in scrutinising aspects of an international agreements that fall within areas of devolved competence. We recommend that time for this scrutiny is factored into the sifting committee’s considerations when setting the scrutiny period for treaties.

Finally, the UK represents both the Crown Dependencies and the Overseas Territories at the international level. This means that the UK negotiates treaties on their behalf or extends treaties to them with their consent. Under the new system we recommend in this report, these actions would require the approval of the House of Commons. As such, a convention should be established whereby the House of Commons would not be called upon to approve a treaty or extension of a treaty relating to a Crown Dependency or an Overseas Territory unless the relevant territory had already expressed its approval for that treaty or treaty extension.