The bill is fairly inaccessible except to those with a keen interest in legal drafting and a cold towel for their brow. Clauses 2–6 make provision for certain parts of EU law to become incorporated into the domestic legal framework as ‘retained EU law’. This includes statutory instruments and other measures pursuant to the European Communities Act 1972, but also other laws ‘relating otherwise to the EU or the EEA’ (clause 2), directly effective EU legislation, including regulations, decisions and tertiary legislation (clause 3) and other rights such as are protected by directly effective directives and treaty provisions (clause 4). The EU Charter of Fundamental Rights is not to be incorporated but the general principles of EU law are (clause 5). Case law of the Court of Justice of the EU (CJEU) pre-exit day will bind lower courts in respect of their interpretation of retained EU law. The Supreme Court and the High Court of the Justiciary in Scotland are bound only in the way that they would be by their own precedents (see clause 6).

The bill excludes challenges to the validity of any EU measure that would be incorporated by the bill as retained EU law, except as subsequently determined by ministers (Sch 1 para 1(1)). Although the general principles of EU law are retained, they can’t give rise to any cause of action (Sch 1 para 3(1)). The right to Francovich damages for failures associated with breaches of EU law is ended on exit day

(Sch 1 para 5(1)). These barriers will not prevent cases otherwise being brought where a remedy lies in ordinary domestic public law (Sch 1 para 5(2)). Measures of EU retained legislation – but not other measures – are to be treated as primary legislation for the purposes of the Human Rights Act 1998 (HRA) and shielded from challenge (Sch 8 para 19).

The HRA will apply to any tinkering done by ministers using the powers in the bill. Any overreach in secondary legislation that breaches convention rights might be quashed by judges. The limits of an ordinary public law challenge remain clear. Judges can strike down anything not clearly authorised by parliament in crystal-clear terms (eg, R (Evans) and another v Attorney General [2015] UKSC 21). Judges left to determine what ‘deficiency’ or ‘failure’ means could quash any measure too broad.

The judiciary are slow to be persuaded that they should set aside measures in secondary legislation that parliament has approved. These cases aren’t cheap and involve costs risks many will be unwilling to take. If barriers to ministerial power are not introduced by parliament, any safety net the courts can deploy may only be available to those with sufficient interest and deep pockets. The House of Lords Delegated Powers and Regulatory Reform Committee has issued a critical report (3rd report of session 2017–19. European Union (Withdrawal) Bill, HL Paper 22, 28 September 2017), calling for the bill’s amendment to better circumscribe the powers afforded to ministers. Its summary is that the bill ‘gives excessively wide law-making powers to ministers, allowing them to make major changes beyond what is necessary to ensure UK law works properly when the UK leaves the EU’ (page 2). The bill proposes such unprecedented delegations of power to the executive that it looks like an unashamed power grab.

Practitioners should prepare for potential legislative proposals in areas of controversy and consider whether reform by secondary legislation might be challenged, including in litigation. If areas of law with an EU legacy are ripe for reform, there may be an opportunity to consider improvement.

How and whether the judiciary may be able to assist will depend entirely on the scope of the Act. The question is: how far will MPs be willing to delegate their powers to ministers and officials in the name of taking back control?