‘Retained EU law’: issues for the Withdrawal Agreement Bill

Publications / Briefings

‘Retained EU law’: issues for the Withdrawal Agreement Bill

23 May 2019

Coming on top of the controversial introduction of the concept of 'retained EU law' in the EU (Withdrawal) Act 2018, the provisions for an implementation / transition period in the UK-EU Withdrawal Agreement pose challenges for UK law that the promised Withdrawal Agreement Bill will need to address, including through amendments to the 2018 Act.

In this May 2019 paper, Swee Leng Harris – Head of Policy and Public Affairs at The Legal Education Foundation, and a member of the Bingham Centre's Expert Working Group on the EU (Withdrawal) Bill and the Rule of Law – first considers 'retained EU law' as a new category of UK law in terms of legal and constitutional status. The paper then makes observations about the constitutional and legal significance of implementation of the Withdrawal Agreement treaty in the promised Withdrawal Agreement Bill (WAB). Finally, the paper identifies necessary amendments to the EU (Withdrawal) Act 2018 (EU(W)A) to accommodate an implementation / transition period and to ensure legal certainty on retained EU law in UK law.

The paper draws a number of conclusions regarding retained EU law and legislative changes needed to accommodate an implementation / transition period and promote legal certainty:

Retained EU law needs to be understood in the round, including the constitutional provisions for retained EU law in the EU(W)A, changes made to retained EU law through secondary (or delegated) legislation, and other primary Brexit-related legislation affecting retained EU law.
The WAB will likely replicate the effect of the European Communities Act 1972 to apply EU law in the UK for the implementation / transition period.
EU law will develop and change during the implementation / transition period, and the WAB will need to enable those changes in EU law to be reflected in UK law.
The WAB should also amend the EU(W)A so that new or modified EU laws that apply in the UK through the WAB during implementation / transition form part of retained EU law.
Consequential amendments will be needed to enable retention of EU law under sections 2 and 4 of the EU(W)A if the ECA is to be repealed on exit day (at the beginning of the implementation / transition period) while the snapshot of EU law is to be taken on 'retention day' (at the end of the implementation / transition period).

The paper builds on the author's April 2018 paper 'Legislating for transition / implementation: implications for the EU (Withdrawal) Bill', also published by the Hansard Society, and develops the issues/arguments raised therein.

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