Materiality as the Gateway under s.146B: Non‑material alterations to SID permissions need no EIA/AA or public participation and may be adopted mid‑litigation without objective bias

Introduction

This commentary examines the High Court judgment of Humphreys J in Rural Residents Wind Aware and Environmental Group & Ors v An Coimisiún Pleanála & Ors (Approved) [2025] IEHC 601 (6 November 2025). The case arises from a s.146B Planning and Development Act 2000 (PDA 2000) request by White Hill Wind Limited to alter a Strategic Infrastructure Development (SID) permission by relocating two turbines (T6 and T7) by approximately 170m and 220m respectively, adjusting associated tracks, cabling, foundations and bridge works, and increasing forestry felling by about 2.45 hectares (total felling increasing from 15ha to 17.45ha).

The developer’s rationale was the withdrawal of certain landowners, including the second-named applicant, from the project lands. The Commission treated the request as a non‑material alteration and, on 10 September 2024, altered the permission accordingly without public participation under s.146B(8) (which is triggered only after a materiality finding). The applicants challenged the decision on domestic and EU law grounds, including alleged excess of jurisdiction, failure to have regard to ministerial wind energy guidelines, objective bias (because the Board acted during pending litigation and with personnel who had decided the parent permission), and failures in Appropriate Assessment (AA) and EIA screening. Two systemic State-law grounds—concerning conservation objectives and the validity of s.146B’s public participation architecture—were modularised for later determination (Module II).

This judgment addresses and dismisses all “Module I” grounds against the Commission (grounds 1, 3, 4, 5 and 5A). It should be read with the related “Rural Residents I” judgment ([2025] IEHC 600), which sets broader context.

Summary of the Judgment

Humphreys J dismissed all live grounds in Module I. The Court held:

The word “term” in s.146B (read with s.146A) is not confined to conditions; the Commission may amend the permission text itself, provided the alteration is not material (and subject to statutory procedure).
Materiality is the statutory gateway. The applicants bore the onus of proving that the alteration was material. They failed to do so; the relocation was relatively minor in the context of the overall project and did not undermine conditions or expand the project’s scale or output.
There was no failure to have regard to the 2006 Wind Energy Development Guidelines (WEDG). The guidelines formed part of the parent decision, and reasons may be incorporated by reference.
Objective bias was not established. A public body may exercise its statutory power to amend a decision even during litigation, absent a stay. Doing so—even if it improves its litigation position—does not constitute objective bias where the power is lawfully exercised for a proper purpose. This is reinforced by the new Order 103 rule 24 RSC, which the Court viewed as declaratory of pre‑existing law.
On AA/EIA, the applicants produced no evidence showing lacunae or that Stage 2 AA was required. The Court accepted the Commission’s Stage 1 screening and the developer’s scientific material, including the addendum to AA screening/NIS. The reliance on CJEU Case C‑66/23 regarding non‑qualifying bird species failed on the facts for want of evidence of effects on Mallard or Grey Heron.
As a matter of statutory design, the Commission’s power to seek EIA information arises only if the alteration is first found to be “material.” Any challenge to that design goes to the validity of s.146B itself (reserved to Module II).

Orders: Module I grounds dismissed; no order as to applicants’ costs in Module I (provisionally), opposing parties’ costs reserved; perfection of the overall order postponed pending completion of Module II.

Analysis

Statutory framework and sequencing under s.146B

Section 146B PDA 2000 allows the Commission to alter the “terms” of an SID permission on request. The Court emphasised these points:

“Term” includes, but is not confined to, conditions (s.146A(4)); it extends to the text and operative elements of the permission. The contrary view “misconceives” the statutory language and purpose.
Materiality is the statutory threshold question (s.146B(2)). If the alteration is not material, the Commission “shall” alter the permission (s.146B(3)(a))—no further assessment or public participation follows.
If the alteration is material, the Commission then enters the EIA/Habitats screening sequence under s.146B(3)–(7A), and public participation under s.146B(8) is engaged before determinations under s.146B(3)(b)(ii) or (4).
Public input on materiality itself is discretionary (s.146B(2)(b)). In this case, the Commission decided not to invite submissions at that threshold stage.

Precedents cited and their influence

Friends of the Irish Environment v An Bord Pleanála [2019] IEHC 80 (Simons J): The Court adopted the sequencing articulated by Simons J—that EIA/Habitats screening obligations are engaged only after a finding of materiality under s.146B. Here, the non‑material finding ended the process, obviating EIA/AA and public participation duties.
Okunade v Minister for Justice [2012] IESC 49: Supports the proposition that commencing proceedings does not impose an automatic stay on administrative action. The Commission was free to decide the s.146B request while litigation was pending.
Salmon Watch Ireland CLG v ALAB [2024] IEHC 421; Word Perfect Translation Services Ltd v Minister for Public Expenditure and Reform [2025] IECA 45; AB v HSE [2025] IECA 48; Kelly v UCD [2025] IESC 6: Applied to the objective bias analysis. The Court stressed the fair‑minded and informed observer test, the need for something “external” to the process, and that a decision adverse to a party or alleged legal errors do not by themselves show bias.
Shadowmill [2023] IEHC 157; Eglington Residents Association [2025] IEHC 209; Morehart [2025] IEHC 418; Dietacaron Ltd v An Bord Pleanála [2005] 2 I.L.R.M. 32: Cited for the proposition that assessments of planning “materiality” and kindred evaluative judgments belong to the decision‑maker’s expert domain and attract judicial restraint absent irrationality or legal error.
McGowan [2025] IEHC 405; Eco Advocacy [2025] IEHC 15: Emphasised the correct approach to reading administrative decisions (holistically and to sustain legality where reasonably possible) and the centrality of proper pleadings.
Elliniki Ornithologiki Etaireia v Ypourgos Esoterikon, C‑66/23 (CJEU, 12 Sept 2024): Applicants invoked this judgment to argue for consideration of non‑qualifying bird species (Mallard, Grey Heron). The Court held the argument failed on evidential grounds: the record did not show likely significant effects on those species from the alteration.
Order 103 rule 24, Rules of the Superior Courts: Although introduced after the impugned decision, the Court treated it as declaratory of pre‑existing law. It confirms that proceedings do not preclude an authority from amending a decision it has legal power to amend, subject to the Court’s supervisory jurisdiction.

Legal reasoning applied to each ground

Core Ground 1: Jurisdiction and materiality under s.146B

The applicants argued the Commission “strayed beyond its jurisdiction” by altering the development rather than its “terms,” and that the relocation was material. The Court rejected both propositions:

Scope of “terms”: Construing s.146B with s.146A(4), “term” includes conditions but is not exhausted by them. The statutory purpose and wording allow amendments to the permission’s operative provisions, including turbine locations.
Materiality: The onus lies on the challenger to establish materiality. On the facts—two turbines moving 170m and 220m, no change to number, type, height or output, modest additional forestry felling, and unaltered compliance with conditions—the Commission’s non‑materiality conclusion was a rational planning judgment. The developer’s affidavits (including Mr Broderick) were unchallenged by cross‑examination and refuted the applicants’ assertions (Dr Bartley). The Court would not substitute its view for the Commission’s expert appraisal.

Core Ground 3: Alleged failure to have regard to the 2006 Wind Energy Development Guidelines

The applicants relied on a passage in the 2006 WEDG suggesting micro‑siting flexibility generally should not exceed 20 metres, arguing that the Commission should have treated a larger movement as material. The Court held:

The Commission had regard to the 2006 WEDG at the parent permission stage, which was incorporated by reference into the alteration decision. Reasons may be located outside the decision document itself.
Section 28 imposes a duty to “have regard to,” not to follow slavishly. The WEDG passage addresses micro‑siting flexibility within a permission; it is not a rule governing s.146B alterations, a distinct statutory process introduced after the WEDG. The ground therefore failed in both fact and law.

Core Ground 4: Objective bias

The applicants contended that the Commission’s decision to process the s.146B alteration mid‑litigation, involving the same inspector and two of three Commission members from the parent decision, created objective bias.

The Court rejected the claim:

Separation of powers: Absent a stay, the Commission is entitled to exercise its statutory powers; it does not need the Court’s permission. The mere fact that an administrative step may improve a party’s forensic position does not amount to bias where the step has an independent legal basis and a proper public purpose.
Order 103 rule 24 RSC now expressly recognises this principle (and is declaratory of existing law): the initiation of proceedings does not preclude an authority from amending a decision it has legal power to amend, unless the Court orders otherwise.
“Something external” is required to ground objective bias; none was shown. Using the same inspector/Commissioners who are familiar with the file promotes efficiency and is a rational administrative practice, not evidence of pre‑determination.

Core Ground 5: Habitats Directive (AA) and related arguments

The applicants alleged the Commission failed to conduct Stage 2 AA, committed errors in Stage 1 AA screening, and failed to consider effects on Mallard and Grey Heron under the Birds Directive (relying on C‑66/23).

The Court dismissed these contentions:

Stage 1 AA screening concluded Stage 2 was unwarranted; the decision and inspector’s report showed engagement with the correct test. The applicants did not establish “lacunae” or evidential flaws sufficient to displace the Commission’s assessment.
On Mallard and Grey Heron, the developer’s scientific evidence (including the addendum to AA screening/NIS and ornithological evidence) indicated no pathways of effect from the relocation. The applicants provided no countervailing scientific basis. C‑66/23 was therefore beside the point on the facts.

Core Ground 5A: EIA screening

The applicants argued that the Commission failed to conduct EIA screening and to record reasons per Article 4(5) of the EIA Directive. The Court held that, under s.146B, the Commission’s EIA obligations arise only after a finding that the alteration is “material.” Because the Commission rationally found the alteration non‑material, the EIA screening duty did not arise. Any challenge to this architecture concerns the validity of s.146B (reserved to Module II), not the Commission’s faithful application of the statute.

Impact and significance

Materiality as decisive gateway: The judgment reaffirms that under s.146B, a non‑material alteration to an SID permission neither triggers EIA/AA nor public participation under s.146B(8). Developers and the Commission should structure and evidence alteration requests around a clear materiality analysis, supported by focused environmental reporting.
Scope of “terms” clarified: “Terms” are not confined to conditions. The Commission’s s.146B power extends to amending the operative components of a permission (e.g., relocation of turbines), provided the change is non‑material or, if material, the statutory steps are followed.
Objective bias boundary set: Authorities can lawfully “self‑correct” or refine decisions during litigation absent a stay. Order 103 rule 24 RSC now codifies that proceedings do not freeze administrative power. This reduces incentives for strategic stays and supports administrative efficiency, while preserving the Court’s power to supervise and, where appropriate, order a stay.
Reasons by incorporation: The Court’s endorsement of reasons “anywhere on the record” (including documents referenced in the decision) eases formalistic attacks on decision letters, provided the reasoning trail is objectively discernible.
Evidential burden in AA/EIA challenges: The decision underscores the need for applicants to adduce cogent scientific evidence and, where suitable, to seek cross‑examination to displace expert affidavits on ecological pathways. Mere assertions, or reliance on EU case law detached from the factual record, will not suffice.
Birds Directive reach in practice: While C‑66/23 stresses consideration of non‑qualifying species where present in significant numbers, this case illustrates that the principle bites only where credible evidence identifies a likely pathway of effect from the specific alteration. Absent that, the argument fails at the threshold.
Forthcoming scrutiny of s.146B: The Court carefully signposts that any systemic challenge to s.146B’s compatibility with EIA/Aarhus (i.e., the absence of public participation in non‑material alterations and the sequencing of screening obligations) must be addressed in a validity challenge against the State (Module II). The forthcoming module may have broader implications for environmental governance and public participation rights.

Complex concepts simplified

s.146A vs s.146B:
- s.146A permits clerical/technical amendments or those facilitating the operation of a decision, but not material alterations.
- s.146B permits alterations to the “terms” of an SID permission on request. The first step is to decide whether the alteration is “material.” If non‑material, the Commission alters the permission without further assessment or public participation. If material, further EIA/AA steps and public participation follow.
Materiality: A planning judgment about whether the change affects third‑party rights or environmental considerations in a significant way. It is context‑specific. The challenger bears the evidential burden to show materiality or legal error in the judgment.
Appropriate Assessment (AA): A two‑stage process under Article 6(3) Habitats Directive. Stage 1 screens for likely significant effects on a European site; Stage 2 (full AA) is required only if such likelihood cannot be excluded on the basis of objective information. The Commission found that Stage 2 was not required here.
EIA screening: An assessment of whether a project (or alteration) is likely to have significant environmental effects so as to require an EIA. Under s.146B, EIA screening obligations arise only if the alteration is first found to be material.
Reasons “by incorporation”: Decision‑makers can satisfy the duty to give reasons by referring to other documents (e.g., an inspector’s report or a parent permission) where those documents contain the reasoning.
Objective bias: The test is whether a fair‑minded and informed observer would apprehend a real risk that the decision‑maker is not impartial. Something external to the decision‑making process is usually required. Lawful use of a statutory power, even during litigation, does not constitute bias.
Order 103 rule 24 RSC: Confirms that bringing judicial review proceedings does not preclude a public body from amending a decision it has legal power to amend, unless the Court orders otherwise. Parties must notify each other of amendments; the Court can manage consequential procedural steps.

Conclusion

This judgment consolidates four key propositions in Irish planning and environmental law:

Under s.146B, the Commission may alter the operative “terms” of an SID permission—relocating infrastructure included—provided the alteration is non‑material or, if material, the statute’s assessment and participation steps are followed.
Materiality is the decisive gateway. If an alteration is non‑material, no AA/EIA or public participation obligations arise under the s.146B architecture. The challenger bears the burden to demonstrate materiality or a legal error in the Commission’s evaluation.
Objective bias is not established by a public body’s lawful exercise of statutory power to amend a decision during litigation. Order 103 rule 24 RSC confirms that proceedings do not impose an automatic freeze on administrative powers.
AA/EIA challenges must be grounded in cogent scientific evidence. Reliance on general principles (e.g., C‑66/23) cannot substitute for proof of a likely pathway of effect from the specific alteration.

Pragmatically, the decision provides a structured path for developers to make modest, evidence‑based alterations where circumstances change (such as land control), and it confirms the Commission’s latitude to manage such requests efficiently. For objectors, the message is equally clear: to defeat a s.146B non‑materiality decision, one must meet a substantial evidential threshold and address the decision‑maker’s reasoning head‑on.

The broader constitutional and EU‑law questions about the validity of s.146B’s participation and screening sequence are expressly reserved to Module II. That forthcoming determination will be closely watched, as it will shape the balance between administrative efficiency for minor alterations and public participation rights in Ireland’s planning system.