The precedents provided in previous legislation, including the Legislative and Regulatory Reform Act 2006, provide examples of how Parliament could introduce safeguards into the EU (Withdrawal) Bill to tighten the scope and application of the powers. 

The Bill requires Parliament to agree in advance the scrutiny procedures that will apply to uses of delegated powers without knowing fully how the powers will be exercised. In doing so it pre-determines what Parliament should debate.

Other Acts which confer upon a minister a significant 'Henry VIII power' to amend primary legislation have made the use of such a power subject to a strengthened scrutiny procedure. None is proposed in this Bill.

Eleven variants on a strengthened scrutiny procedure currently exist but none are suitable for the powers in the EU (Withdrawal) Bill. The provision of statutory consultation periods, a committee veto, and a trigger to extend the scrutiny period from 40 to 60 days make them impractical for the Brexit process.

The proposed new procedure will apply to the widest powers in the EU (Withdrawal) Bill. It will require amendment of the Bill and could also be applied to powers in other Brexit legislation that follows.

The key feature is that in the first 20 days of the scrutiny period Parliament (via its delegated legislation committees), not ministers, will decide how the exercise of the powers will be scrutinised. The committees will have the power to upgrade a Statutory Instrument (SI) subject to the 'negative' scrutiny procedure to the higher 'affirmative' scrutiny procedure. Once the scrutiny level has been determined, the SI will be subject to the new scrutiny system in the House of Commons and existing procedures in the House of Lords.

The current system of ‘praying’ against SIs using an Early Day Motion, and 90-minute Delegated Legislation Committee debates followed by a pointless vote on a consideration motion, would be abolished. In its place a new permanent Delegated Legislation Scrutiny Committee (DLSC) should be established for the scrutiny of all SIs in this and other bills. It would:

• be in the control of Members not whips, with the chair and members elected in the same way as other select committee;

• be supported by a set of sub-committees, some of whose members would also be members of relevant departmental select committees;

• have administrative, legal and research support via a committee secretariat;

• sift and scrutinise both negative and affirmative SIs and those subject to strengthened scrutiny procedures; and

• turn over to the whole House for further consideration those SIs of concern, with procedures in place to ensure that any SI reported to the House would have to be debated and voted on. Members would be granted a ‘conditional amendment’ power alongside procedural hurdles to ensure that ministers cannot ignore their concerns. 

If implemented, our proposals will: 

• provide for more rigorous and systematic scrutiny, and reflect the fact that Parliament is delegating power to the executive, not subordinating itself to the government’s wishes;

• make a government response to the legitimate concerns of parliamentarians about SIs a requirement not an option;

• give MPs a meaningful role and voice in the process, and make more efficient and effective use of the time they spend scrutinising SIs;

• retain the top-level architecture of the present delegated legislation system, including affirmative, negative and strengthened scrutiny procedures and the standard 28- and 40-day scrutiny periods for SIs, addressing government concerns about time and speed;

• require amendments to Standing Orders but not to the Statutory Instruments Act 1946, which would unhelpfully take up further parliamentary time. 

Blackwell, J. & Fowler, B. & Fox, R. (2017) Taking Back Control for Brexit and Beyond: Delegated Legislation, Parliamentary Scrutiny and the European Union (Withdrawal) Bill (London: Hansard Society)