Sovereignty, influence and Brexit
The Brexit impact on sovereignty is not as simple as it might first seem. This is because the government had admitted that, before Brexit, the UK was sovereign while it was an EU member state. It is therefore difficult to see how Brexit improved UK sovereignty.
However, although sovereignty and ‘power and influence’ are different, they are related. Sovereignty means a nation’s ability to take its own decisions and, if it wishes, reverse them. Power and influence in this context means a nation’s ability to achieve its goals through its relationships with other nations.
Brexit means that the UK no longer pools sovereignty with EU member states to influence EU policy and regulatory outcomes.
With Brexit, the UK became a third country (like any other non-EU country) when it left the treaties of the EU. It is only able to have a new relationship with the EU through new legal agreements (such as the Trade and Cooperation Agreement) with its institutions, regulatory bodies and programmes. In parallel, the EU is determined to retain the integrity of the Single Market, not undermine the EU’s rules-based framework and not see the exit of another member state.
Closer to home, within the UK, there was an issue of how to re-establish the sovereignty of parliament following the referendum. (See Appendix A for analysis of the 2016 referendum result). Some believed that a ‘final say’ should have been offered to the public to express its view on the outcome of the negotiations. Others believed that parliament should have reasserted its authority.
Since Brexit, the Conservative government (the executive) had a large majority until the general election of 2024. With this, parliamentary influence over the government had weakened. For example, the Sunak government arbitrarily terminated HS2 without parliamentary debate, even though HS2 had repeatedly received cross-party parliamentary support, .
How Brexit weakens UK power
There are several ways in which Brexit reduces or weakens the UK’s power and influence, for example:
- The UK has little influence over the future policies, rules and regulations of the EU, its closest and biggest trading partner. After Brexit, the UK needs to comply with many EU rules and standards in order to trade with EU member states.
- For example, Switzerland, which is not an EU member, takes many EU laws on to its statute books to facilitate access to the Single Market.
- Internationally, UK influence has reduced because the UK no longer has the weight of the EU behind it or the ability to influence the EU27 from within.
- For example, the UK is one of the five members of the United Nations Security Council and the US had looked to the UK as a power broker to influence the rest of the EU. This role has diminished: the US now looks to France as the main influencer over the EU.
- After Brexit, the UK continues to pool its sovereign power selectively with the EU for integrated European responses to policy issues that the UK cannot resolve on its own.
- For example: challenges of energy efficiency and sustainability; support for Ukraine; energy security; data security and the internet; and, terrorism.
- However, it is challenging to do this when the UK no longer has a seat at many inter-related EU27 tables.
- As an external third country, the UK is in a weaker position to negotiate trade deals with non-EU countries.
- The UK is dependent on an equivalence decision on central counterparties which lasts until 30 June 2028, but the EU can withdraw it unilaterally at short notice (see Trade section).
- After Brexit, the UK continues to be subject to external international authorities on trade.
- For example, when the UK successfully negotiates free trade agreements with other countries, any disputes are subject to independent arbitration. The World Trade Organisation resolves disputes for its members (which include the EU).
- Similarly, if the UK became an independent member of EFTA, it would be subject to the EFTA Court of Justice.
The 2007 Lugano Convention ceased to apply in the UK after 31 December 2020, except in relation to proceedings in process. The convention:
- attempts to clarify which national courts have jurisdiction in cross-border civil and commercial disputes and ensure that judgements taken in such disputes can be enforced across borders;
- is an international treaty negotiated by the EU on behalf of its member states (by Denmark separately because it has an opt-out) and with, subsequently, Iceland, Norway and Switzerland.
In January 2020, the UK applied to accede to the Lugano Convention as an independent member after leaving EU, which required the agreement of all signatories. Although the UK had the support of Iceland, Norway, Switzerland and the European Commission, member state governments rejected the UK’s application in 2021.