Planning: Reform of the Hybrid Bill procedure for major infrastructure consents

Ministerial submission

To: The Leader of the House of Commons

Issue

1. The Hybrid Bill procedure, used to authorise major infrastructure such as Crossrail and HS2, grants deemed statutory authority for the works it describes but has, in recent practice, left a large volume of detailed third-party consent to be negotiated after Royal Assent, contributing materially to cost and schedule overrun on HS2 Phase One. This submission concerns whether that procedure should be reformed before it is next used for a major scheme, and if so, by what mechanism, given that responsibility for Standing Orders rests with the House rather than with Government.

Background

2. A Hybrid Bill is a Public Bill that also affects specific private interests in a way ordinary legislation does not, most often because it authorises a defined physical scheme — a railway line, a tunnel, a single building — whose route or site affects some landowners and occupiers differently from others. Recent examples include the Crossrail Act 2008, the High Speed Rail (London–West Midlands) Act 2017 (HS2 Phase One), and the Holocaust Memorial Act 2026. Following First Reading, the Bill is examined to confirm hybridity, then referred to a specially appointed Select Committee before which persons “specially and directly affected” may petition for amendment; once the Committee reports, the Bill proceeds through both Houses broadly as an ordinary Public Bill would.

3. The Act resulting from this process typically disapplies the ordinary requirement for planning permission under the Town and Country Planning Act 1990 for the specific works it authorises, granting what is in effect deemed permission. It does not, however, extinguish the interests of statutory undertakers, local authorities, and other bodies whose land, assets, or regulatory functions the works affect. Instead, the Act’s protective provisions preserve these bodies’ right to require the promoter to obtain their consent to the detailed method, timing, or design of works in their vicinity before those specific works may proceed. This is the mechanism by which outline authorisation granted by Parliament translates, after Royal Assent, into thousands of separate, individually negotiated approvals.

4. On HS2 Phase One, this has proved costly. Widely cited estimates put the number of separate additional consents HS2 Ltd has had to secure from statutory undertakers, local authorities, and other protected persons since Royal Assent at well over 3,000; the National Audit Office and the Institute for Government have both identified routine challenge to consent applications, and the expensive mitigation works sometimes required to secure them — the bat mitigation structure at Sheephouse Wood, Buckinghamshire, reported to have cost in the region of £100 million, is the most widely reported single example — as a material contributor to cost growth. The whole programme’s cost had already grown from an original 2015 budget of around £56 billion to an estimated £100 billion by the time its Northern legs were cancelled in 2023; HS2 Ltd’s most recent reset, covering the Phase One route now under construction, puts the remaining cost to complete at £87.7–£102.7 billion in 2026 prices. The Institute for Government separately calculates that just over 1,300 hours of legislative time have been spent on four HS2-related Bills across nine Sessions in the last decade.

5. Recent hybrid bills are, in practice, almost exclusively rail schemes, because the Planning Act 2008 created the Development Consent Order (DCO) regime specifically to remove the need for one-off primary legislation for most other major infrastructure. Nuclear power stations are a case in point: Sizewell C, the most recent example, was consented in 2022 not by hybrid bill but by a Development Consent Order under the Planning Act 2008, examined by the Planning Inspectorate and granted by the Secretary of State — the same route discussed in the companion submission on fast-track consenting. The DCO route is not immune to contested mitigation costs of its own: at the sister Hinkley Point C plant, EDF’s fish protection measures for the cooling water intake — a low-velocity intake system, a fish recovery and return system, and an acoustic deterrent, together costing in the region of £700 million — have been publicly disputed, with some industry commentary arguing the spend is disproportionate to the small number of fish involved and environmental groups rejecting that framing; at Sizewell C itself, the dispute has run the other way, with the Environment Agency declining to require an equivalent deterrent despite campaigners’ warnings of large-scale fish mortality. Front-loaded consenting relocates this kind of contested mitigation cost into the examination process rather than eliminating it. Hybrid Bills remain necessary only for the narrower category of schemes needing primary legislation for reasons a DCO cannot satisfy: rail schemes of exceptional scale and cross-boundary complexity, or, in one recent non-transport case, a need to override protections in a separate historic Act that only Parliament could disapply. The Holocaust Memorial Bill, authorising a single building in Victoria Tower Gardens, needed hybrid status for the latter reason — it required Parliament to override the London County Council (Improvements) Act 1900 — and was itself ruled hybrid in May 2023, spent over a year in Select Committee hearing petitions, was carried over across a general election, and did not reach Royal Assent as the Holocaust Memorial Act until 2026, a multi-year process for a single building driven by the same petitioning and consent architecture that produced HS2’s post-Assent consent volume, albeit without the scale of financial consequence. The recurrence of comparable delay across two hybrid bills of very different size, sector, and subject matter suggests a structural feature of the procedure rather than a problem specific to HS2’s scale or management.

6. The Institute for Government’s July 2025 report on hybrid bill procedure, drawing on the HS2 and Crossrail experience, recommends reforms it assesses could be implemented with relative ease within the existing framework: committing future hybrid bills to a single joint Commons/Lords committee rather than sequential single-House committees, appointing an assessor of petitions to support the committee’s handling of large volumes of petitions, and adopting a more robust standard approach to challenging or grouping objections. These recommendations address the time a bill takes to pass; they do not, on their own, address the volume or leverage of consents required after it passes.

7. You have not yet been asked to take a position on hybrid bill reform specifically, but the question has acquired direct relevance to the Government’s programme. The Prime Minister pledged, before and since taking office, to revive the Birmingham–Manchester leg of HS2, cancelled in October 2023, using a “Crossrail-style” funding model drawing on central government, local government, and land value capture. Several press reports of the pledge have quoted a cost of approximately £102.7 billion for the revived leg; this appears to be the same figure as the official cost-to-complete estimate for HS2 Phase One at paragraph 4 above, rather than an independent costing of the Manchester extension, and officials are not aware of a separate published estimate for the revived leg — a first order of business, whichever option below is preferred, will be commissioning one. Parliament already holds a relevant hybrid bill vehicle: the former HS2 Phase 2b Bill was repurposed in May 2024 to secure powers for a section of Northern Powerhouse Rail between Manchester Piccadilly and Millington, sharing infrastructure with the cancelled HS2 route. Any revival of the full Birmingham–Manchester line would most plausibly proceed by adapting or succeeding this existing vehicle, making the choice of procedure a near-term rather than hypothetical question.

The General Case

8. The case for reforming the procedure centrally, rather than leaving each promoter to manage the existing framework as well as it can, rests on three grounds:

• (a) the recurrence of comparable delay and consent volume across HS2 and the unrelated Holocaust Memorial Bill (paragraphs 4 and 5) suggests the problem is structural to the procedure itself, which promoter-level improvement in consents management, however well executed, cannot fully address;
• (b) the Prime Minister’s manifesto commitment to revive the Birmingham–Manchester line converts a longstanding but unpressing case for reform into a live, time-bound decision, since any new or repurposed Bill will proceed on whatever basis the procedure currently offers unless that basis is changed first;
• (c) repeated, well-publicised cost and schedule overrun attributed in part to a Parliamentary procedure risks bringing both the promoter and Parliament into disrepute, and could over time deter future governments from using the Hybrid Bill procedure at all for infrastructure that genuinely needs it.

9. The case against central reform rests on three grounds:

• (a) the Hybrid Bill procedure’s petitioning rights and protective provisions exist specifically because the private interests it affects are not adequately protected by ordinary Public Bill procedure; reform aimed at reducing delay engages genuine due-process and property-rights considerations, not merely administrative friction;
• (b) hybrid bills vary enormously in scale and character, from a multi-billion-pound national railway to a single London building; a generic procedural fix risks a mechanism poorly suited to smaller or more contained future bills;
• (c) Standing Orders are a matter for the House, not the Government, and the Government is also the principal promoter of the infrastructure hybrid bills typically authorise; a reform process driven too visibly by the Executive risks the appearance of the promoter rewriting the rules under which its own promotions are scrutinised.

Options

Option A: Retain the current procedure and rely on promoter-level improvement

10. Under this option, no central Parliamentary or legislative reform is pursued. Any revived Birmingham–Manchester Bill, or other future hybrid bill, would proceed on the existing basis — deemed planning permission for the scheduled works, with protective-provision consents negotiated after Royal Assent — with promoters expected to apply lessons already being developed by HS2 Ltd, including earlier engagement with statutory undertakers and dedicated in-house consents teams.

11. For:

• (a) requires no change to Standing Orders or legislation, avoiding any delay to a revived Birmingham–Manchester Bill from reform of the procedure itself;
• (b) preserves petitioners’ and protected persons’ existing rights in full, avoiding the due-process concern identified at paragraph 9(a);
• (c) HS2 Ltd’s own consents-management practice has reportedly improved through earlier engagement and dedicated teams, suggesting the existing framework is capable of some improvement without formal reform.

12. Against:

• (a) the scale of cost and delay attributed to post-Assent consents on Phase One suggests promoter-level improvement alone has not been, and is unlikely to be, sufficient to prevent recurrence at comparable scale;
• (b) leaves in place the same structural incentive for any revived Birmingham–Manchester Bill: each protected person retains the same post-Assent leverage that contributed to Phase One’s overruns;
• (c) does nothing to address the reputational risk identified at paragraph 8(c), which recurs with every hybrid bill that overruns publicly.

Option B: Establish a Royal Commission on the Hybrid Bill procedure

13. Under this option, the Government establishes a Royal Commission, reporting within eighteen months to two years, to examine the Hybrid Bill procedure across recent precedent — Crossrail, HS2, and the Holocaust Memorial Act — and recommend reform, drawing on the Institute for Government’s 2025 analysis and further evidence-gathering of its own. No Standing Order or legislative change is made pending its report.

14. For:

• (a) provides the cross-party legitimacy that a Government-initiated reform of a House-owned procedure otherwise lacks, addressing the institutional concern at paragraph 9(c);
• (b) allows systematic evidence-gathering across the full range of past hybrid bills, reducing the risk of reform over-fitted to the rail sector specifically;
• (c) a Commission reporting within two years would still conclude before a revived Birmingham–Manchester Bill could realistically reach Royal Assent, preserving the option of applying its recommendations to that Bill.

15. Against:

• (a) a Royal Commission is advisory only; it cannot itself amend Standing Orders or enact legislation, so implementing its recommendations would still require a further decision under Option C or D;
• (b) even an eighteen-month to two-year timetable risks a revived Bill being introduced, or substantially progressed, before the Commission reports, particularly given the existing repurposed Phase 2b vehicle already before Parliament;
• (c) Royal Commissions have a mixed recent record of translating recommendations into implemented reform, and establishing one now may be read as deferring rather than addressing the problem.

Option C: Pursue procedural reform through the Usual Channels

16. Under this option, you work with opposition business managers, the Chairman of Ways and Means, and the Procedure Committee to secure cross-party agreement on the reforms already identified by the Institute for Government: committing future hybrid bills to a single joint Commons/Lords committee, appointing an assessor of petitions, and adopting a more robust standard approach to challenging or grouping objections — implemented by Standing Order change agreed by consensus rather than by Government motion alone.

17. For:

• (a) builds on recommendations already developed by an independent body, avoiding the delay of commissioning fresh analysis under Option B;
• (b) securing reform through the Usual Channels rather than by Government motion addresses the institutional-legitimacy concern at paragraph 9(c) without the extended timetable of a Royal Commission;
• (c) a joint committee and assessor of petitions address the process delay illustrated at paragraphs 4 and 5 without touching the deemed-consent question, avoiding the due-process concerns that attach most directly to Option D.

18. Against:

• (a) does not address the post-Assent consents problem that is the principal driver of the cost figures at paragraph 4; the reforms proposed reduce the time a bill takes to pass, not the number or leverage of consents required after it passes;
• (b) cross-party agreement through the Usual Channels can stall or be renegotiated with any change of Government or Official Opposition business manager, offering less durability than a Standing Order or statutory change with a defined review point;
• (c) a joint committee model has not been used for a hybrid bill in the current Parliament and would require testing on a live bill, plausibly the revived Birmingham–Manchester Bill itself, before its effect on timetable is known with confidence.

Option D: A default deemed-consent mechanism for scheduled protective provisions

19. Under this option, future hybrid bills authorising nationally significant infrastructure would, as standard practice required by Standing Order or, more durably, established as a default position under a free-standing framework Act, include a schedule of protective-provision consents deemed granted at Royal Assent unless the protected person formally objects within a fixed period before introduction or during the Select Committee’s petitioning stage. Consents bound up with genuine engineering or operational safety, such as railway interface sign-off, would be carved out of the deeming mechanism and would continue to require case-by-case approval.

20. For:

• (a) directly targets the post-Assent consents problem identified as the principal driver of cost and delay on HS2 Phase One, in a way Options B and C do not on their own;
• (b) moves the point of negotiation earlier, into the existing petitioning process before the Select Committee, where protected persons already have a formal right to be heard, rather than removing that right;
• (c) the safety-critical carve-out distinguishes genuine engineering sign-off, which should not be deemed, from the wider category of planning, highways, and amenity consents more often used as leverage, addressing the due-process concern at paragraph 9(a) in a targeted rather than blanket way.

21. Against:

• (a) defining the boundary between safety-critical and other consents is itself contestable and would need to be settled, category by category, for every future hybrid bill, recreating at the drafting stage some of the dispute currently experienced post-Assent;
• (b) protected persons who currently rely on post-Assent negotiation to secure mitigation or compensation beyond the Bill’s original terms would lose that leverage, and may object more forcefully during the pre-Assent petitioning window as a result, a risk the more robust approach to objections proposed under Option C is intended to help manage;
• (c) engages Article 6 ECHR (right to a fair hearing) and Article 1 Protocol 1 (protection of property) most directly of the four options, since a deemed consent removes a discrete decision point a protected person could otherwise expect to control.

Resource and Cost Implications

22. Option A involves no direct additional cost but carries the unbudgeted risk of a repetition of Phase One’s overrun pattern on any revived Birmingham–Manchester Bill. Option B requires funding for a Commission secretariat and evidence-gathering over an eighteen-to-twenty-four-month period, modest relative to the infrastructure costs at stake, but delays the point at which any reform benefit is realised. Option C is primarily a call on officials’ and business managers’ time and the Procedure Committee’s programme, with minimal direct cost. Option D requires either Standing Order drafting or a framework Bill, with associated Parliamentary time, and departmental legal resource to develop the safety-critical carve-out categories; if effective, it is the option most likely to reduce the risk of a multi-billion-pound overrun pattern recurring on a revived Birmingham–Manchester line.

Legal and Constitutional Considerations

23. Standing Orders are a matter for the House of Commons, and separately the House of Lords, to determine by resolution; they are not within the Government’s unilateral gift to amend, even where the Government holds a working majority. The Government’s practical routes to reform are to move a motion with cross-party support secured through the Usual Channels (Option C), to refer the question to the Procedure Committee for scrutiny, or to legislate a substantive default through a framework Act (the legislative variant of Option D), which would bind the content of future hybrid bills rather than merely the process by which they pass, and would itself need to proceed through Parliament as an ordinary Public Bill. A Royal Commission (Option B) is established under the Crown prerogative and may recommend any of the above but cannot itself effect them.

24. Environmental and other regulatory consents of the kind implicated in cases such as the Sheephouse Wood mitigation works are, in England, the responsibility of bodies such as Natural England; a comparable future scheme extending into Wales or Scotland would engage Natural Resources Wales or the Scottish Environment Protection Agency under devolved environmental legislation. A hybrid bill authorising works only in England, as a revived Birmingham–Manchester line would be, does not itself require devolved legislative consent, but any deemed-consent default developed under Option D would need to state expressly that it applies only to English protective-provision consents and does not purport to bind devolved regulators.

25. A revived line through Greater Manchester would also engage the Greater Manchester Mayoral Strategic Authority as a protected person and consenting body in its own right. The interaction between a Hybrid Bill’s deemed planning permission and the call-in and Spatial Development Strategy powers considered in the companion submission on fast-track consenting is a further instance of the devolution-versus-local-democracy problem set out in the structural-problems digest, here in its most acute form: the Hybrid Bill procedure grants deemed permission directly by Act of Parliament, with no determinative role for either the local planning authority or the mayoral Strategic Authority at all, only a right to petition. No option considered in this submission alters that position; officials should note it as context rather than as a matter this submission resolves.

Requested direction

26. Ministers are invited to indicate whether the current Hybrid Bill procedure should continue unchanged pending any revival of the Birmingham–Manchester line (Option A); whether a Royal Commission should be established to examine the procedure before any such Bill is introduced (Option B); whether reform should be pursued now through the Usual Channels, building on the Institute for Government’s recommendations (Option C); or whether a default deemed-consent mechanism for protective-provision consents should be developed, whether by Standing Order or by framework legislation (Option D); and, given that Standing Orders are a matter for the House rather than the Government, how the preferred option should be carried forward with the Official Opposition’s business managers and the Procedure Committee.