The legal problem with Boris Johnson’s new Brexit withdrawal agreement bill

The main business for Parliament this week will be to consider the European Union (Withdrawal Agreement) Bill. Enacting the bill will make it possible for the UK to ratify the withdrawal agreement and thus to leave the EU later this month in an orderly fashion, with EU law set to continue in force in the UK throughout the implementation period. This is due to end on 31 December.

The bill was introduced to the House of Commons on 19 December and differs in important respects from the bill considered before the election in October. So what's changed?

The bill now empowers ministers by regulation to authorise any UK court, not just the Supreme Court, to depart from judgments of the Court of Justice of the EU, case law which UK legislation otherwise gives effect in domestic law even after the implementation period ends. This is a mistake and should be rethought.

In one way, it is no surprise that a Government with a stable majority and a new electoral mandate has recast the bill. However, there has only ever been a limited range of options in relation to legislation in connection to the withdrawal agreement, for the obvious reason that the legislation is framed – and limited – by the terms of the agreement.

Where there is room for significant variation is in relation, first, to the way in which the legislation bears on parliamentary involvement in negotiations about the future relationship between the UK and the EU. And, second, the way in which current EU law will have force in the UK after the expiry of the implementation period.

The European Union (Withdrawal) Act 2018 makes provision for EU law as it stands on exit day, apart from the EU Charter of Fundamental Rights, to continue in force in domestic law. The logic of the Act is to transpose EU law, which is a function of the EU treaties and the actions of EU institutions, into domestic law, to be termed “retained EU law”, but which the UK would then be free to change. The bill which is before the House this week makes provision, as per the withdrawal agreement, for an implementation period during which time EU law continues to have effect in the UK. The bill thus delays the introduction of “retained EU law” until the end of the implementation period.

Retained EU law includes judgments of the Court of Justice of the EU (more commonly known as the European Court of Justice or ECJ). This is unsurprising. Those judgments form an important part of the existing corpus of EU law, especially when they interpret the EU treaties or EU legislation in surprising or otherwise unpredictable ways. If the point of retaining EU law is to maximise legal continuity in the first instance, to avoid introducing unnecessary legal confusion, then it makes sense to preserve the continuing effect of that case law.

Subject to any future agreement the UK might reach with the EU, the UK will be free after the implementation period comes to an end to change its law, including retained EU law, as it sees fit. The vital question is how this law should be changed and, especially, who should change it. The answer is that it should be changed by ministers and Parliament, not by courts. Unfortunately, the 2018 Act does invite some judicial lawmaking, an approach which the new bill extends.

Section 6(3) of the 2018 Act requires UK courts to decide questions about the validity, meaning and effect of retained EU law in accordance with retained EU case law. However, section 6(4) provides that the Supreme Court (and High Court of Justiciary in Scotland) is not bound by retained EU case law and section 6(5) specifies that in deciding whether to depart from retained EU case law the Court must apply the same test as it would apply in deciding whether to depart from its own case law.

In late 2017, in evidence to the Exiting the EU Committee of the House of Commons, I argued that subsections (4) and (5) were misconceived.

Parliament should not authorise the Supreme Court to change settled law in the course of adjudication and it was far from clear exactly when the Court would change the law on the basis of the test set out in the Act. Instead, retained EU law should be changed by ministers exercising secondary lawmaking powers and/or by Parliament enacting primary legislation. While it was essential to bring to an end the jurisdiction of the ECJ, authorising the Supreme Court to depart from past ECJ judgments, which formed part of the law at exit day, would introduce unnecessary legal doubt and improperly empower the Court to make new law.

Clause 26 of the new bill amends section 6 of the Act. Two new subsections, (5A) and (5B), would authorise ministers by regulation to enable any UK court or tribunal to depart from retained EU case law, to provide for the extent to which a relevant court or tribunal is not bound by that case law, to specify the test which the court or tribunal must apply in deciding whether to depart from that case law, and specifying considerations which the court (including the Supreme Court) must take into account in applying the relevant test.

Before making such regulations, subsection (5C) requires the minister to consult five senior judicial office-holders (the President of the Supreme Court, etc.), and subsection (5D) says that no regulations may be made after the end of the implementation period.

There is an uneasy relationship between regulations that may be made under these new subsections and the Supreme Court’s freedom, per section 6(4) and (5), to depart from retained EU case law.

Regulations could conceivably empower lower courts to depart from retained EU case law in a broader class of cases than would arise for the Supreme Court under section 6(5). Regulations to change the circumstances in which the Supreme Court may depart from ECJ judgments might be lawful – section 6(5A)(d)(i) seems to contemplate some such change – but would risk being invalid to the extent that they displace section 6(5) itself. This is rather a mess.

The amended section 6 is both better and worse than the existing section. Much turns, clearly, on how ministers would exercise the power in question. If they were to authorise all UK courts, not just the Supreme Court (and High Court of Justiciary), to depart from retained EU case law, then this might well magnify the legal uncertainty which section 6 already introduces.

However, it would also avoid the anomaly that litigants may have to wait until their appeal reaches the Supreme Court before challenging the continuing application of retained EU case law. If ministers provided extensive guidance to courts as to how and when ECJ judgments are to be followed, then this might minimise unnecessary legal argument about what the law is. But it would be much better for ministers simply to change retained EU law directly, by way of secondary lawmaking powers or by proposing primary legislation that would clarify or replace retained EU law, including case law.

Strikingly, the amended section 6 would permit ministers to delegate to senior judicial office-holders the power, with or without further ministerial consent, to determine the test to be applied before the relevant court departs from retained EU case law and/or considerations the courts must take into account.

This would be an improper delegation of lawmaking power to the courts and Parliament should not permit it, not least since it risks being seen to be the easy option, despite the fact that it would unfairly impose responsibility for lawmaking on an individual judge.

The requirement to consult senior judges is also problematic. Insofar as ministers are changing the law by exercising this statutory power, there is no reason why they should have to consult judges before so doing. And the duty to consult is a hostage to fortune. Such duties invite litigation and in any case, the exercise of this statutory power is very likely to be challenged in the courts, with many judges liable to be hostile to regulations that address how they are to deal with case law.

The authority of ministers, exercising statutory powers, to change the law should not be in doubt. But lawmaking by way of the amended section 6 will be at best indirect and will readily be caricatured as a constitutionally improper interference with adjudication. The risk of caricature is not itself a sufficient reason for Parliament to hold back from amending section 6, but it bears noting that the amended section 6 may well invite complex, and to some extent political, litigation.

There are very good reasons to review and amend retained EU law, including case law, especially before the implementation period expires. But responsibility for changing this law should be taken up by ministers and Parliament, who should change the law directly rather than by attempting to authorise, and then to frame, how or when UK courts should change the law, or, worse, simply delegating this responsibility to courts.

Parliament should not assent to this new ministerial power – at least in the terms in which it is currently framed – and should instead amend the bill to remove the Supreme Court’s freedom to depart from retained EU case law. In this way, the new bill might better contribute to the project of restoring parliamentary democracy and the rule of law.

Richard Ekins is Head of Policy Exchange’s Judicial Power Project and Professor of Law and Constitutional Government at the University of Oxford