In an earlier post, I explained that the European Council’s decision to extend the Article 50 period is a separate matter from the way in which ‘exit day’ is defined in the European Union (Withdrawal) Act 2018 (EUWA). Among other things, this means that whether or not ‘exit day’ is redefined in domestic law will not affect the date on which the UK leaves the EU, the date of departure being a matter that is determined by EU law — and thus by last week’s European Council decision.

However, I also pointed out in that post that failing to redefine ‘exit day’ for domestic purposes would risk significant legal problems. In particular, a great deal of secondary legislation has been made in anticipation of Brexit — not least in order to adapt what is now EU law to the changed circumstances that will apply upon withdrawal — and is due to enter into force on ‘exit day’. If that legislation were to enter into force on 29 March 2019 that would be highly problematic, given that such legislation would, in part, be incompatible with EU law, and given that EU law will continue to apply after 29 March now that that date does not mark the UK’s departure from the EU. The existence, in effect, of two incompatible sets of laws would risk chaos, and would flout the rule-of-law requirement of legal certainty.

It is therefore to be welcomed that the Government has laid before Parliament a statutory instrument to adjust the definition of ‘exit day’. The snappily titled European Union (Withdrawal) Act 2018 (Exit Day) (Amendment) Regulations 2019 provides that the current definition of ‘exit day’ in the EUWA is to be modified in one or other of two ways. The first possibility is concerned with the (unlikely) scenario in which the Withdrawal Agreement is approved before 29 March 2019:

[I]f, in accordance with Article 1 of European Council Decision (EU) 2019/476 of 22 March 2019(1), the period provided for in Article 50(3) of the Treaty on European Union is extended until 22 May 2019, [exit day shall be] 11.00 p.m. on that day

The alternative is concerned with the (more likely) scenario in which the Withdrawal Agreement is not approved by the House of Commons by 29 March 2019:

if [the period provided for in Article 50(3) of the Treaty on European Union is] not [extended until 22 May 2019, 11.00 pm., [exit day shall be] 11.00 p.m. on 12 April 2019

The Regulations will thus align the domestic definition of exit day with the European Council’s decision concerning the extension of Article 50. ‘Exit day’ will be 22 May if the Withdrawal Agreement is endorsed by the House of Commons, and 12 April if it is not. However, in order to be made (and thus have legal effect), it is not sufficient that the Regulations be produced by the Government. Paragraph 14 of schedule 7 to the EUWA sets out the conditions for making regulations amending the definition of ‘exit day’:

A statutory instrument containing regulations under section 20(4) [NB section 20(4) of the EUWA gives Ministers the power to make Regulations adjusting the definition of ‘exit day’] may not be made unless a draft of the instrument has been laid before, and approved by a resolution of, each House of Parliament.

This means that in order for the redefinition of ‘exit day’ in domestic law to take effect, both the House of Commons and the House of Lords will have to vote, by a majority, to approve the Government’s draft Regulations. Those opposed to delaying Brexit may, for that reason, vote against the Regulations. But, as noted above, this will manifestly not have the effect of unpicking the agreement that the UK reached with the European Council last week: under EU law, withdrawal will not now occur until 12 April at the earliest. It is, however, the case that voting down the Regulations could produce significant legal and practical problems, as I noted in my earlier post on this subject. This analysis is shared by the Government. In a paper accompanying the draft Regulations, it says:

[A] rejection of the ‘exit day’ SI [i.e. statutory instrument] would cause serious problems and uncertainty with regard to the domestic statute book from 11pm on 29 March. A large volume of EU exit legislation preparing the domestic statute book for the moment EU law ceases to apply is due to enter into force automatically on ‘exit day.’ A rejection of the SI would therefore create a clash in domestic law; contradictory provisions would apply both EU rules and new UK rules simultaneously, and in some cases new UK rules would replace EU rules prematurely. This could generate confusion and uncertainty for businesses and individuals, resulting in litigation. In some cases, it could restrict the rights of individuals or impair the ability of public bodies to operate within the framework of EU rules.

What the Government does not say in its paper is that to the extent that Brexit-inspired domestic law and EU law conflicted, EU law would necessarily take priority. This would follow because, after 29 March, the UK would remain a Member State of the EU. It would therefore be subject (as a matter of EU law) to the principle of the supremacy of EU law and the European Communities Act 1972 (in domestic law) would continue to assign priority to EU law over inconsistent domestic law. Faced with conflicting sets of laws, i.e. EU law proper and domestic legislation enacted in the expectation of Brexit, courts would therefore give priority to EU law between 29 March 2019 and the date of the UK’s actual departure from the EU. The scope for uncertainty and confusion, however, would be profound.

This leads on to a further apparent difficulty. Section 1 of the EUWA says that the European Communities Act 1972 is repealed on ‘exit day’. Repealing the ECA before the UK actually leaves the EU would be highly problematic, because the ECA is the principal means by which the UK discharges its obligation to give effect to EU law in domestic law. Premature repeal of the ECA would thus place the UK in breach of that international-law obligation and would risk additional chaos. In fact, however, as things stand this problem will not materialise because, for reasons that remain obscure but can perhaps be inferred, the Government has not brought section 1 of the EUWA into force, meaning that it does not currently have any legal effect. Brexiteer parliamentarians are thus denied the option of triggering the repeal of the (for them) detested European Communities Act by failing to play ball when it comes to approving the Regulations redefining ‘exit day’. Nevertheless, the problems that would arise if the domestic meaning of ‘exit day’ were not aligned with the date of the UK’s departure under EU law would be serious, and can only be avoided if Parliament approves the draft Regulations.