I have been looking carefully at the EU (Withdrawal) Bill recently. To say that it is byzantine in nature would be to do a disservice to the Byzantine Empire. The Bill is (or at least seems to me to be) unnecessarily complex, ambiguous and tortuous in both structure and drafting. The contrast with the elegant simplicity of the European Communities Act 1972 (“ECA”) which prepared the domestic legal ground for membership of (what is now) the EU is striking. The complexity of the EU (Withdrawal) Bill makes the aphorism “the devil is in the detail” peculiarly apposite. And while criticism of the Bill has thus far tended to focus upon the extraordinary powers with which it invests Ministers for the purpose of addressing so-called deficiencies in the post-exit statute book, the concerns raised by the Bill in fact go far beyond that.

When a piece of legislation suffers from such deficiencies as ambiguity, vagueness, prolixity and undue complexity, that is necessarily problematic, given the imperative need, rooted at the very core of the rule of law, for legal certainty and clarity. But such concerns are amplified many times by the legal, economic, social and constitutional significance of this particular Bill. For it is no ordinary piece of legislation. Rather, it implants within the UK legal system a corpus of law — “retained EU law” — that is very substantial in scale and highly significant in content, and which is liable to around for many years to come. Ministerial powers to amend retained EU law may be time-limited by a sunset clause, but there is no expiry date on “retained EU law” itself.

The following questions give a flavour of some of the difficulties (as I see them). I do not intend to suggest by posing the following questions that they are necessarily unanswerable. Indeed, I will attempt to answer some of them, if time permits, in posts that I hope to publish in September. My point, for the time being, is a more modest one: that the answers to the questions are not (at least in my view) clear or straightforward, and that these are therefore issues that need to be clarified as the Bill progresses through Parliament. The importance of that point is underscored by the fact that, technical though many of the questions set out in this post undoubtedly are, they raise issues of profound importance that will shape the post-Brexit legal landscape for many years to come. Here, then, are 20 questions (or, more accurately, 20 groups of questions) about the Bill.

“Exit day”

1  Can there be more than one “exit day”, given that “exit day” is to be prescribed by regulations (clause 14(2)) and given that “any power to make regulations” conferred by the Bill “may be exercised so as to … make different provision for different cases or descriptions of case, different circumstances, different purposes or different areas”? Could, for instance, “exit day” mean one thing for the purpose of clause 1 (so as to effect ECA repeal on 29 March 2019) and something else for the purpose of clause 7(7) (so as to, in effect, extend the two-year sunset clause that applies to the use of the clause 7 amendment powers)? Could differential exit dates be used to enable the power under clause 9(1) to persist beyond what is, for other purposes, taken to be exit day, thereby permitting clause 9(1) to be used to amend the Bill itself (which can be done according to clause 9(2)) long after what counts as exit day for other purposes has been and gone?

EU-derived domestic legislation

2  Why does clause 2 purport to save not only (for instance) secondary legislation enacted under the ECA, which would fall away upon repeal of the ECA, but also primary legislation that implements or otherwise relates to EU law, which will remain in force in spite of ECA repeal and in spite of EU withdrawal? Surely such legislation does not need to be “saved”? After all, primary legislation that implements or otherwise relates to EU law does not depend for its continuing legal basis or validity upon the ECA or upon the UK’s membership of the EU. (The same goes for secondary legislation enacted under primary legislation other than the ECA.)

3  Is the purpose of casting the clause 2 net so wide to render primary legislation that implements EU law (e.g. the Equality Act 2010) vulnerable to the clause 7 amendment powers? But if (as seems likely) that is the purpose, is that purpose achieved? Or does primary legislation that falls within the clause 2 definition of “EU-derived domestic legislation” fall outside the clause 6(7) definition of “retained EU law” (and hence beyond the reach of the clause 7 amendment powers) because primary legislation does not continue (in the words of clause 6(7)) “by virtue of” clause 2? Can primary legislation (and, for that matter, secondary legislation made other than under the ECA) really continue “by virtue of” clause 2 if, as it surely would, it would continue even if clause 2 did not exist?

EU directives and direct effect

4  Does clause 4(2)(b) really mean (as the Explanatory Notes appear to suggest) that a directly effective right contained in EU directives will be brought into domestic law only if the specific right in question has been judicially determined to be directly effective? Or do the words “of a kind” in clause 4(2)(b) mean that rights contained in directives that satisfy the criteria for direct effect will be brought into domestic law, irrespective of whether there is a judicial determination as to whether those criteria are satisfied in respect of the specific right in question? If (as the Explanatory Notes suggest) it is the former, such that there must be a pre-exit judicial decision on the specific point, why adopt such a limited approach? If the purpose of the Bill is to domesticate EU law, why privilege only a subset of rights in directives that are capable of direct effect by reference to whether there is a judgment on the relevant point — something that, in effect, turns upon happenstance?

5  Subject to the confusion referred to in the previous question, clause 4 provides for the domestication of (some) provisions in directives that are capable of direct effect. However, clause 4 does not make any exception in this regard in respect of provisions in directives that have been domesticated by means of domestic legislation that will be saved by clause 2. Does this mean that clauses 2 and 4 may operate so as to result in two versions of a given EU-derived norm within the domestic legal system, i.e. the version contained in EU-derived domestic legislation and the version domesticated by clause 4? If so, what would happen if those two versions of the EU-derived norm were to differ? Which would prevail? Would both versions have “supremacy” under clause 5?

6  When directly effective rights contained in directives are domesticated by clause 4, to what extent are they domesticated? Will domestic norms fashioned from such rights suffer from the same restrictions (in particular the “no horizontal effect” rule) that apply to rights contained in unimplemented directives?

Retained direct EU legislation

7  Is retained direct EU legislation (or is retained direct EU legislation to be treated as if it were) primary legislation, secondary legislation, or something else? If it is something else, what is it exactly? How does that “other” category relate to primary and secondary legislation? If the Bill really does purport to create some “other”, new, sui generis taxonomical category of domestic law, is it possible and/or sensible to purport to do that by implication? If it is possible to do so, why, in any event, an attempt to do so being made? If the Bill seeks to create a new, sui generis category of legislation, why not say so clearly on the face of the Bill?

8  Is the designation (by schedule 8, clause 19) of retained direct EU legislation as primary legislation for the purposes of the Human Rights Act 1998 (“HRA”) intended to reflect the fact that it is primary legislation for all purposes? Or is retained direct EU legislation designated as primary legislation for HRA purposes because it is not otherwise primary legislation, meaning that it requires special designation under the HRA? And if (as schedule 8, clause 19) indicates, it is necessary to assign retained direct EU legislation to a domestic legal taxonomical category for HRA purposes, why is it not similarly necessary to assign it to such a category for other (indeed, all) purposes?

9  Does the Bill authorise Ministers to change (or confer) a domestic legal status (e.g. primary legislation or secondary legislation) upon retained direct EU legislation and/or to change the legal status of EU-derived domestic legislation? Is it intended that the clause 17 power to make consequential provision will be capable of being used for that purpose? If so, is it intended that all EU-derived instruments will be so designated, because legal certainty requires such designation? What will happen if some EU-derived instruments are and some are not so designated? If legal certainty requires designation, why does the Bill not at least ascribe to EU-derived instruments a default status?

The supremacy principle

10  Is clause 5(1), which provides that “the principle of the supremacy of EU law does not apply to any enactment or rule of law passed or made on or after exit day”, merely declaratory, or is it intended to have some normative effect? Is not “the principle of the supremacy of EU law” rendered inapplicable within the UK legal system by both the UK’s withdrawal from the EU (and so the falling away of its Treaty obligations) and by repeal of the ECA (and so the removal of any domestic legal acknowledgment of the supremacy principle)? If so, is not the statement in clause 5(1) — that the supremacy principle does not apply to post-exit domestic law — both otiose and misleading, because the supremacy of EU law is extinguished in its entirety both by exit and by ECA repeal? And does that not mean that clause 5(2), which is predicated on the assumption that clause 5(1) abolishes the supremacy principle only to a limited extent, is in fact founded upon a misapprehension?

11  Given that the Bill excises EU law (as distinct from retained EU law) from the domestic legal system, in what sense can “the principle of the supremacy of EU law” continue to apply post-exit? From the perspective of the UK legal system, is there any “EU law” to which the supremacy principle can relevantly attach post-exit and/or after ECA repeal? Is “retained EU law” supposed to inherit the “supremacy” of “EU law”? If “retained EU law” is (as it surely is) domestic law, can it inherit the “supremacy” of “EU law”? If it can, can it (as the Bill seems to assume) do so through implication, given that none of this — beyond bland and nonsensical statements about “the supremacy of EU law” — is spelled out on the face of the Bill?

12  If “the principle of the supremacy of EU law” can meaningfully apply post-exit, what does it apply to, given that it cannot meaningfully apply to “EU law” per se? Does it apply to all retained EU law? Or only to some retained EU law? If the latter, why does the Bill not spell this out by addressing the compass of the supremacy principle following exit day?

13  If the supremacy principle applies only to some categories of retained EU law, which ones are they? Is it intended to apply only to forms of retained EU law that derive from forms of EU law that themselves enjoy supremacy? Does this mean, for instance, that EU-derived domestic legislation will not benefit from the supremacy principle (because, as domestic law, it has never, qua domestic law, had supremacy), but that retained EU law under clauses 3 and 4 that derive from directly effective EU law will enjoy supremacy?

14  When does pre-exit domestic legislation become post-exit domestic legislation for the purpose of determining the applicability of the principle of the supremacy of EU law? Clause 5(3) provides that a modification made on or after exit day does not prevent the supremacy principle from applying in respect of pre-exit domestic legislation, but only “if the application of the principle is consistent with the intention of the modification”. How is it envisaged that courts will determine whether the application of the supremacy principle is consistent with the intention of the modification?

Judicial review and the common law

15  Is retained EU law subject to judicial review, including on common law constitutional rights grounds? In particular, is retained direct EU legislation subject to judicial review? Or is retained direct EU legislation immune from judicial review? If it is immune, is that because it is “primary legislation”? Or is it because retained direct EU legislation is “supreme”?

16  If retained direct EU legislation and the common law conflict, which prevails? Does retained direct EU legislation prevail because it is “supreme”? Even if it is supreme, is that relevant? Does the supremacy principle bite upon (thereby enabling retained EU law to prevail over) the common law, or is the common law not a form of domestic law that is vulnerable to the operation of the post-exit version of the supremacy principle provided for by the Bill? In particular, does the common law consist of “rules of law” (within the meaning of clause 5(1)–(2)) that are “made before exit day” such that the supremacy principle can bite upon those rules? Does only some of the common law consist of rules of law made before exit day? If so, how should we work out when a common law rule is “made” for this purpose?

Ministerial powers

17  If a Minister uses clause 7(1) to confer regulation-making powers on someone else, are those sub-delegated regulation-making powers subject to the same procedural and scrutiny requirements (specified in schedule 7) as the regulation-making powers conferred by clause 7(1)? Given that clause 7(1) powers can be used to make regulations that “make any provision that could be made by an Act of Parliament” (clause 7(4)) does that mean that a Minister can give others powers to do things that she could not do under clause 7(1)? Given that sub-clauses other than sub-clause (4) of clause 7 make it clear that there are things that cannot be done using the clause 7(1) regulation-making powers, what does the Bill actually intend when it says that the power can be used to do anything that can be done by an Act of Parliament? Is not that statement contradicted by the other terms of clause 7, thereby rendering the statement fundamentally ambiguous and unhelpful? Would it not be better for the Bill to specify what is meant by this?

18  According to schedule 8, paragraphs 3 and 5, pre-exit and post-exit subordinate law-making powers are to be read, so far as the context permits or requires, as being capable of being exercised to modify retained direct EU legislation. Does this mean, in effect, that most subordinate law-making powers conferred by primary legislation other than this Bill can be used to modify EU law (albeit only for purposes contemplated by the parent Act)? If so, does this not substantially undermine the sunset clauses that apply to powers conferred by the Bill itself?

19  Schedule 7, paragraph 13 says that any power to make regulations granted by the Bill “may be exercised so as to modify retained EU law”. But only some powers in the Bill, most obviously clause 7(1), are concerned with the modification of retained EU law. Does schedule 7, paragraph 13 really mean that every power in the Bill can be used for that purpose, including regulation-making powers that do not explicitly confer any power to amend retained EU law? And does that mean that the sunset and procedural limitations applicable to the primary amending power in clause 7 can be circumvented? Could, for instance, the power to define “exit day” — which is subject to no sunset clause and no requirement for parliamentary scrutiny — be used so as to modify retained EU law, bearing in mind that “[t]he fact that a power to make regulations is conferred by this Act does not affect the extent of any other power to make regulations under this Act” (schedule 7, paragraph 14)?

20  How broad are the powers conferred by clause 17? (Clause 17 says that Ministers can by regulations “make such provision as the Minister considers appropriate in consequence of this Act”, and that includes “modifying any provision made by or under any enactment” including Acts of Parliament enacted before or during the session in which the Bill is enacted.) What limits apply to the categories of things that could lawfully be considered by a Minister to be “appropriate in consequence of this Act”? Can clause 17 be used to amend the Bill itself?

Final thought

As mentioned above, I do not intend, by posing these questions, to suggest that they are necessarily unanswerable. Indeed, I have been giving a good deal of thought to what the answers might be, and will, time permitting, try to write about what I think some of the answers are in September. My immediate point, however, is that the answers to these questions should be clearer and far more obvious than they presently are. I do not doubt that drafting the Bill was extremely challenging, and nor do I envy those whose task it was. But this Bill is too important to get wrong, and the present version of the Bill contains so many ambiguities and uncertainties that it surely cannot be allowed to constitute the finished article. Indeed, one of the paradoxes of the Bill is that while highly complex and prolix, it ends up leaving some of the most fundamental questions unanswered.

Whatever one’s views about the wisdom or otherwise of Brexit, it is surely entirely uncontroversial that if Brexit is to happen, it should occur in a way that is, to the maximum possible extent, orderly: a chaotic Brexit is in nobody’s interests. Realising that aim will partly turn upon what, if any, withdrawal and transitional agreements the UK is capable of negotiating with the EU. But it will also turn, to a significant extent, upon providing for a post-Brexit domestic legal system that is capable of accommodating extraordinary legal upheaval in a way that minimises uncertainty and confusion. Judged against that benchmark, the present Bill falls very far short. And so, as parliamentarians begin to contemplate returning from their summer break, it is to be hoped that they prove to be both willing and able to subject the Bill to the sort of examination it demands. If the devil is in the detail, then parliamentary scrutiny will have to be suitably forensic and the amendments and improvements to the Bill commensurately substantial. If not, then the domestic legal consequences of Brexit may be every bit as damaging as the political and economic implications, according to Remainers, have the potential to be.

I am grateful to Jack Williams for his very helpful comments on an earlier draft of this post. The usual disclaimer applies. This post is written in a purely personal capacity.