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EU law

The UK’s relationship with EU law is changing as part of Brexit. The Withdrawal Agreement Bill (WAB), if passed, would implement those changes in UK law.

The UK is currently an EU member, and EU law applies in the UK.

This relationship is implemented in the UK’s European Communities Act (ECA). After the UK’s exit from the EU, the UK’s relationship with EU law would be mediated by the Withdrawal Agreement.

As a result, the current direct relationship between the UK and EU law would be replaced, post-exit, by an indirect relationship.

The WAB would implement this new relationship between EU law and the UK.

As I explained elsewhere, implementation of the Withdrawal Agreement in UK law would mean that the agreement would operate like a series of gates allowing entry to EU laws so that those laws have effect in UK law.

By thinking of the Withdrawal Agreement as a series of gates that would open and close at different times, it is possible to more clearly understand the operation of the agreement across time.

If all goes according to the government’s plans, the UK will soon leave the EU and the ECA will be repealed on exit day.

This repeal of the ECA already became UK law under the 2018 EU (Withdrawal) , which made significant changes to the UK constitution, including the introduction of ‘retained EU law’ into UK law.

The Withdrawal Agreement provides the terms for the UK’s exit including protecting citizens’ rights, avoiding a hard border on the island of Ireland, and financial matters, as well as the ‘stand still’ transition period — also called the implementation period.

The Withdrawal Agreement refers to and incorporates various EU laws.

For example, the Withdrawal Agreement’s transition period provisions incorporates EU law generally with certain specified exceptions until the end of 2020 or 2022 at the latest, depending on whether transition is extended.

The various particular EU laws identified as relevant to citizens’ rights apply for so long as people to whom those citizens’ rights provisions apply are alive.

Article 4 of the Withdrawal Agreement is perhaps the most legally significant provision in the treaty with constitutional significance for the UK.

Article 4 states that the provisions of the Withdrawal Agreement itself and the provisions of EU law that it incorporates shall have the same effect in UK law as the effect of EU law within the EU and EU member states.

This includes the ability of individuals to rely directly on provisions contained or referred to in the agreement, in line with the principle of ‘direct effect’ under EU law.

The WAB would implement the Withdrawal Agreement’s legal effect in UK law as explained in detail by Professor Kenneth Armstrong.

For example, the WAB would save the effect of the ECA for the transition period, even though the ECA will be repealed on exit day.

The WAB would also implement Article 4 by providing that ‘rights, powers, liabilities, obligations, restrictions, remedies and procedures’ provided for, by or under the Withdrawal Agreement have legal effect in the UK and prevail over UK law.

This language in the WAB is similar to the language used in the ECA to implement EU law in UK law.

The WAB would introduce into UK law another new category of law: ‘relevant separation agreement law’.

Relevant separation agreement law would include directly applicable and directly effective aspects of the Withdrawal Agreement treaty.

WAB amendments to the 2018 Withdrawal Act mean that relevant separation agreement law would prevail over:

  • removal of the principle of supremacy of EU law from UK law,
  • exclusion of the Charter of Fundamental Rights from retained EU,
  • and the UK courts.

However, clauses 29 and 36 introduce an element of ambiguity as to the implementation of the Withdrawal Agreement by the WAB.

Sir William Cash stated in debate on 22 October that he had authored clauses 29 and 36 in negotiation with the government to reaffirm national sovereignty.

Clause 29 would give Parliament oversight of EU law during transition, and Clause 36 provides that application of separation agreement law through the WAB does not constitute a derogation from the principle of Parliamentary sovereignty.

Professor Mike Gordon has observed that while the message of clause 36 “may appeal to some sceptics of an ongoing relationship between the UK and the EU, it is difficult to see that it has any practical effect in terms of diminishing the actual legal status of the obligations flowing from the Withdrawal Agreement in domestic law.”

Yet even if it lacks practical effect, this ambiguity in the WAB does not serve the rule of law principles of legal certainty and honouring the UK’s obligations under international law.

By Swee Leng Harris, Visiting Senior Research Fellow at The Policy Institute at King’s College London, and Head of Policy and Public Affairs at The Legal Education Foundation


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