The IAC was established in 2020 in the aftermath of the UK’s exit from the EU. It has the remit to scrutinise treaties laid before Parliament under Part 2 of the Constitutional Reform and Governance Act 2010 (the CRAG Act) and report the most significant to the House. The IAC is the only body in Parliament dedicated to scrutinising treaties and the only parliamentary committee in either House which regularly considers international agreements. Its role is therefore important, especially given that treaties are often nowadays instruments of domestic policy-making affecting matters such as human rights, immigration, environment or economic regulation. Treaties can also raise matters of significant public importance.

The UK’s scrutiny process harks back to another era. The CRAG Act codified a convention established in 1924 which has changed little since. The legislation applies only to treaties which are subject to ratification. Each House of Parliament has a short period – 21 sitting days – within which it can vote against ratification. A vote in the House of Lords can be overridden by the Government. The Commons can in theory delay ratification indefinitely if it repeatedly votes against the treaty, but this power has never been exercised. The Lords has voted against a treaty only once, in the case of the Rwanda Asylum Partnership Agreement in January 2024.

Evidence to the IAC inquiry was that because these powers are weak, Parliament does not pay enough attention to treaties.

The IAC’s report is in fact the latest in a series by parliamentary committees on this topic since 2019 when the UK’s exit from the EU brought the issue of treaty scrutiny to wider attention. It is worth noting that the EU had competence to negotiate certain types of treaty on behalf of the UK, in particular trade agreements. The repatriation of this competence shone a light on the weakness of the Westminster treaty scrutiny process in comparison to the powers exercised by the European Parliament. The European Parliament has to give its consent to certain categories of treaty which incentivises information-sharing and cooperation and gives it far more influence.

No government since 2019 has seriously engaged with the recommendations of previous inquiries and the weight of the evidence behind them. In general, they have stuck to the view that, in the words of the former FCDO Minister for treaty policy, Catherine West MP – the CRAG Act process, is “a flexible and proportionate framework” which “balances the Executive’s responsibility for negotiating treaties under the Royal prerogative and the need for parliamentary accountability”.

Superficially there has been a willingness to adopt some practical improvements to make the treaty scrutiny process more effective. However, the Government has not lived up even to such modest commitments. For example, it has accepted in principle that some treaties are so significant that they merit a longer scrutiny period and has pointed to the extension power, exercisable by FCDO Ministers, which the CRAG Act provides. Yet when put to the test, the Government has refused to grant Parliament more time for scrutiny even in cases where they acknowledge a significant public interest in a treaty and there is no urgency to ratify. This happened most recently in the case of the agreement with Mauritius on the transfer of sovereignty over the Chagos Archipelago.

We decided that the five-year anniversary of the IAC was a good moment to revisit the operation of the CRAG Act, drawing on the Committee’s unique perspective and expertise in treaty scrutiny. A key goal of our inquiry was to explore whether the Government’s objections to reform were valid. We concluded that they were not.

In responding to previous inquiries, the Government has relied on the same few arguments.

The Government cites the dualist nature of the UK constitution, i.e., that treaties do not take effect in domestic law unless implemented by Parliament and argues that the UK scrutiny process is consistent with other dualist countries, in particular other “Westminster-style” parliaments. Evidence to our inquiry contradicted that assertion. Studies show that the majority of other countries (including those with dualist constitutions) have stronger treaty scrutiny processes, including a requirement for parliamentary approval of some, if not all, treaties. The UK is an outlier in this respect.

Ministers argue that Parliament’s role in the adoption of implementing legislation gives further opportunities for scrutiny. It is true some treaties need implementing through legislation, yet many need no legislation, or require legislation only for certain provisions. Moreover, the policy choices are already locked in by the time Parliament gets to consider implementing measures. And those measures may be adopted by secondary legislation which often receives limited scrutiny. Scrutiny of implementing legislation is therefore no substitute for treaty scrutiny.

The Government insists that the 21 sitting day timeframe is enough for most treaties. Since EU exit they have accepted that more time is merited for new free trade agreements (FTAs) and put in place informal arrangements for enhanced scrutiny of them, which include providing Parliament with the treaty text after signature. This typically means that for FTAs Parliament has 3-4 months to conduct an inquiry. The Government refuses to accept that enhanced scrutiny arrangements should apply to other major treaties even though the implications may be equally significant. This is unjustifiable.

The Government objects to changing the CRAG Act process because it insists that it needs to retain flexibility to strike deals in the national interest. We do not dispute that the Government requires some latitude to conclude treaties. But we concurred with many witnesses that the discretion the Government enjoys under the CRAG Act is too broad. There is a balance to be struck between flexibility on the one hand and the transparency and scrutiny which the public interest requires on the other. The CRAG Act process tilts this balance too far in the Government's favour gives it too much discretion to act in ways which enable it to evade detailed scrutiny.

The CRAG Act is overdue for reform. The IAC report challenges the Government to engage more substantively with its recommendations than previously and to commit to a serious dialogue with Parliament about how the scrutiny process can be rebalanced. The Government says that it recognises the importance of parliamentary scrutiny of treaties. Now is the time to put reforms into practice that remove the constraints on Parliament which prevent the exercise of its scrutiny function.