Summary of Judgment by Judge Humphreys

Factual and Procedural Background

This judgment concerns a statutory planning judicial review challenge to a decision dated 25 February 2025 by a national planning body ("Company B") granting planning permission for a strategic infrastructure development consisting principally of a wind farm of thirteen turbines, a 110 kV substation and associated works located across townlands in The County. The planning application had been made directly to Company B by the developer ("Company F") following pre‑application consultations under the Planning and Development Act. The application was supported by an Environmental Impact Assessment Report (EIAR), a Natura Impact Statement (NIS) and related documentation. Third‑party submissions and submissions by prescribed bodies were made; one third‑party (the Applicant) made submissions in English and Irish.

Company B appointed inspectors who produced a report (dated 23 December 2024) recommending grant of permission subject to conditions. Company B issued an order granting permission on 25 February 2025 in English only; an Irish language version was published on Company B's website on 9 July 2025 and the parties were notified. The Applicant issued proceedings on 23 April 2025 seeking, inter alia, certiorari quashing the decision, declarations including constitutional and EU law challenges (in particular relating to Irish language publication and alleged deficiencies in Appropriate Assessment and EIA) and costs. Module directions and case management steps followed; multiple affidavits and submissions were filed by the parties. The State conceded a declaration limited to site‑specific conservation objectives for one SPA (the Gearagh SPA) being published after the decision. The hearing of Module I issues took place on 3 December 2025 and judgment was delivered on 17 December 2025 by Judge Humphreys.

Legal Issues Presented

1. Whether the decision of Company B dated 25 February 2025 should be quashed on domestic grounds because the Board Order was issued initially in English only and not simultaneously in Irish (constitutional and statutory challenge).
2. Whether Company B unlawfully delegated or failed to exercise discretion regarding an oral hearing (this ground was not pursued).
3. Whether the Appropriate Assessment (AA) conducted by Company B was defective so as to contravene Article 6 of the Habitats Directive and related transposing provisions (including alleged failure to dispel reasonable scientific doubt in relation to particular SPAs and species).
4. Whether the Environmental Impact Assessment (EIA) was defective (claims included alleged failure to assess certain risks such as landslide risk and effects on particular bird species); this ground was largely withdrawn except for a limited point on a turbine relocation condition.
5. Whether the State respondents (national authorities) failed to have in place site‑specific conservation objectives and conservation measures for the Gearagh SPA (and whether non‑qualifying species present in a significant manner were properly considered).
6. Whether certain provisions of the Official Languages (Amendment) Act 2021 and associated commencement instruments were invalid, and consequences for Company B's language obligations.

Arguments of the Parties

Applicant (Company A)'s Arguments

• The order was made initially in English only despite bilingual policies and the site's location mainly in a Gaeltacht area; this breached constitutional and statutory language obligations and fair procedures.
• The AA and EIA were defective: the assessments did not dispel reasonable scientific doubt concerning potential adverse effects on the Mullaghanish to Musheramore Mountains SPA and the Gearagh SPA and on particular species (including Hen Harrier, Golden Plover and Merlin), and therefore the consent was unlawful under EU law.
• The State had not put in place necessary site‑specific conservation objectives/conservation measures for the Gearagh SPA at the time of the decision.
• Certain statutory language changes brought into force by commencement instruments were advanced as procedurally invalid and thus the reinstatement or continuation of prior language protections was sought.
• Relief sought included certiorari quashing the decision, declarations, costs, and stay of the decision pending determination.

Company B (Planning Body)'s Arguments

• Non‑publication in Irish at the moment of the order did not invalidate the decision; the missing Irish text was subsequently published and there was no prejudice to the Applicant.
• The AA and EIA were lawfully carried out; the inspector and Company B addressed the relevant matters on the material before them, including ecologist/scientist reports, the NIS and EIAR, and any alleged lacunae were not established by admissible expert evidence.
• The belated affidavit relied upon by the Applicant (Affiant 4) was inadmissible as ex post facto material and not a true reply; it introduced new evidence unreasonably late and should be excluded or afforded no weight.
• The Applicant failed to properly particularise certain EU law grounds and did not discharge the onus of proof to show defects in AA/EIA.
• Even if any shortcoming existed, it would be harmless error and quashing the consent would be disproportionate and contrary to the proper exercise of judicial discretion in light of wider policy (including climate context).

State Respondents (Company C, Company D, Company E)'s Arguments

• The State conceded a limited declaration that site‑specific conservation objectives for the Gearagh SPA were published only on 25 April 2025 (after the decision) but otherwise denied breaches of EU obligations.
• The State argued the Applicant's pleadings lacked sufficient particularity for some grounds; assertions of non‑transposition or failure to establish measures were not made out.
• The State maintained that conservation measures and SSCOs are not jurisdictional pre‑requisites for appropriate assessment and that the materials before Company B were sufficient.

Notice Party (Company F / Developer)'s Arguments

• The developer objected to late affidavits by the Applicant and argued the Applicant could and should have raised its technical points during the administrative process; late expert evidence was inadmissible.
• The developer supported Company B's position that AA and EIA were lawfully carried out on the material before Company B and that the Applicant had not displaced that assessment evidentially.
• The developer relied on its EIAR/NIS and further information responses, and on expert affidavits filed on its behalf, to show there was no reasonable scientific doubt about effects on the SPAs.

Table of Precedents Cited

Precedent	Rule or Principle Cited For	Application by the Court
O'Sullivan v. HSE [2023] IESC 11	Limits on draft-judgment engagement; procedure for circulation of draft judgments.	Cited to explain limits on what parties may do when a draft judgment is circulated and to support directions given to parties.
O'Sullivan v. Sea Fisheries Protection Authority [2017] IESC 75	Warning against treating draft procedures as re‑argument or opening new phases.	Used to support the court's guidance on the draft circulation process.
Attorney General v. Crosland (No. 2) [2021] UKSC 58	Why restriction on publication of draft judgments can be in the interests of administration of justice.	Quoted to justify directions restricting dissemination of the draft judgment.
Friends of the Irish Environment v. Government of Ireland [2020] IESC 49	Importance of obligations to address climate change in planning context.	Referenced in framing the climate context and public interest in renewable energy.
Toole v. Minister for Housing [2024] IEHC 610	Climate context and legal relevance to planning decisions.	Used as part of the climate law context that informs discretionary assessment of remedies.
Reilly v. An Coimisiún Pleanála [2025] IEHC 659	Set out an "eight‑fold test" for when relief by judicial review will be granted.	Adopted and applied as the organising framework for assessing whether certiorari should be granted.
Sweeney v. Fahy [2014] IESC 50	Judicial review concerns legality rather than merits/correctness.	Cited to stress the limits of judicial review and that it is not an appeal on merits.
State (Keegan) v. Stardust Compensation Tribunal [1986] I.R. 642	Deference to administrative decision‑takers and limits on substitution of views.	Used to support the proposition that courts should not substitute their view for decision‑takers on merits.
Meadows v. Minister for Justice [2010] IESC 3	Judicial review scope and onus principles.	Cited for the proposition that judicial review is concerned with legality and onus rests with applicant.
R (Cart) v. Upper Tribunal [2011] UKSC 28	Limitations on treating merit arguments as points of law in judicial review.	Cited to guard against dressing up merits as points of law.
Stapleton v. An Bord Pleanála & Savona [2025] IEHC 178	Warning against turning judicial review into merit re‑hearing of planning judgments.	Used to underline deference on evaluative planning judgments.
Moran v. An Bord Pleanála [2025] IEHC 510	Examples of evaluative judgment review; onus of proof.	Cited in support of standards for reviewing planning judgments and onus of proof points.
R (Hoareau and Bancoult) v. Secretary of State for Foreign and Commonwealth Affairs [2019] EWHC 221	Judicial review is not politics by other means.	Used to emphasise separation of powers and limits to judicial policy substitution.
Sinnott v. Minister for Education [2001] IESC 63	Deference to administrative policy choices.	Relied upon when explaining that policy choices are for other branches and courts should respect that.
T.D. v. Minister for Education [2001] IESC 101	Separation of powers and limits on judicial review.	Cited in discussion of judicial restraint and policy matters.
B. v. Child & Family Agency & Ors. [2025] IESC 2	Separation of powers; policy choices reserved to executive/legislature.	Used to caution against courts substituting decisions for elected branches.
G. v. Ireland [2025] IESC 49	Courts should not treat open‑ended constitutional provisions as requiring substitution of legislative judgment.	Invoked to reinforce the limited role of courts on policy matters.
Tesco Stores Ltd v. Secretary of State for the Environment [1995] 1 WLR 759	Evaluative judgments are for the decision‑maker; weight given to evidence is for them.	Used to support deference to evaluative planning judgments.
Baby O v. Minister for Justice [2002] IESC 44	Evaluative judgments and limits to court interference.	Cited for the principle that weight and evaluation are matters for decision‑maker.
M.E. v. Refugee Appeals Tribunal [2008] IEHC 192	Evaluative judgments and review standards.	Referred to in connection with standards of review.
Heathrow Airport Ltd [2020] UKSC 52	Deference on evaluative environmental judgments.	Used to support that planning judgments involving evaluative questions are for the decision‑maker.
Sherwin v. An Bord Pleanála [2024] IESC 13	Evaluative judgments in planning are reviewed on an irrationality standard unless tainted by legal error.	Cited to support review standard for planning evaluative judgments.
Graymount House Action Group v. An Bord Pleanála [2024] IEHC 327	Examples of judicial review principles in planning context.	Referenced in the general canvass of planning review jurisprudence.
Mulloy v. An Bord Pleanála [2024] IEHC 86	Decision should be read in a way that makes sense; avoid hyper‑technical invalidation.	Applied in the court's general approach to reading decisions sensibly.
O'Donnell v. An Bord Pleanála [2023] IEHC 381	Read decisions in the round; focus on what decision is fundamentally saying.	Relied on when construing Company B's decision sensibly rather than on minutiae.
Save Roscam Peninsula CLG v. An Bord Pleanála (No. 6) [2024] IEHC 335	Decisions should be read in context and not parsed to find invalidity on technicalities.	Cited to support approach resisting hair‑trigger certiorari for technicalities.
E.M. v. Minister for Justice and Equality [2024] IESC 3	Unhelpful statements should not be read as inconsistent with statutory factors if a valid reading is available.	Applied to urge sensible reading of administrative texts.
Friends of Killymooney Lough v. An Coimisiún Pleanála [2025] IEHC 407	Workable interpretation and limits on imposing impossible obligations.	Used to support the court's view on workable statutory interpretation in environmental context.
Moore v. Dun Laoghaire Rathdown County Council [2016] IESC 70	Mere technicalities are not normally a basis for relief.	Cited in considering proportionality of relief for technical breaches.
Save Cork City Community Association CLG v. An Bord Pleanála [2022] IESC 52	Disproportionality may counsel against quashing a decision on a technical procedural error.	Applied in discretionary assessment of remedy.
Watchhouse Cross Shopping Centre v. An Coimisiún Pleanála [2025] IEHC 520	Recent planning judicial review authority cited for procedural principles.	Referenced as part of contemporary planning review authorities.
R (Blewett) v Derbyshire County Council [2003] EWHC 2775	Avoid legalistic over‑parsing of decisions.	Invoked to caution against micro‑analysis of administrative decisions.
G.T. v. Minister for Justice [2007] IEHC 287	Not desirable to parse decisions word‑for‑word to find infelicities amounting to invalidity.	Used to justify reading decision as a whole.
A.I.M.Z. v. Refugee Applications Commission [2008] IEHC 420	General principle to avoid over‑parsing administrative decisions.	Applied to support the court's reading in context approach.
S.A. v. Refugee Appeals Tribunal [2009] IEHC 383	Pleading and evidential standards in judicial review.	Cited in discussion of pleading rigour.
Obuseh v. Minister for Justice [2010] IEHC 93	Evidential standards and review procedures.	Referred to in survey of authorities on judicial review procedure.
Bondo v. Minister for Justice & Ors. [2012] IEHC 454	Similar procedural authorities on review.	Referenced among authorities on approach to judicial review pleadings and evidence.
P.M. v. Refugee Appeals Tribunal [2014] IEHC 497	Procedural and pleading standards in judicial review.	Referenced in context of pleading rigour.
O.S. v. Refugee Appeals Tribunal [2015] IEHC 839	Standards of evidence and pleading in judicial review.	Included in the compendium of authorities on procedure.
X.E. v. International Protection Appeals Tribunal [2018] IEHC 402	Procedural standards; evaluation of evidence.	Referenced when discussing admissibility and evaluation of evidence.
B.D.C. (Nigeria) v. International Protection Appeals Tribunal [2018] IEHC 460	Evidential and procedural rules in review proceedings.	Cited in evidential context.
Waltham Abbey v. An Bord Pleanála; Pembroke Road Association v. An Bord Pleanála [2022] IESC 30	Statutory provisions should be read to produce workable and coherent interpretation.	Applied to the court's insistence on workable readings of obligations.
Frescati Estates Ltd. v. Walker [1975] IR 177	Legislation should avoid strange incongruities; interpret practically.	Invoked in support of workable statutory construction.
In re Murphy [1977] IR 243	Rejecting interpretations that render legislation unworkable.	Used to support workable interpretation doctrine.
100 Meter Tall Group v. An Bord Pleanála [2025] IESCDET 85	Statutory words should be given meaning consistent with essence of provision.	Cited in relation to workable statutory interpretation and pleading scope.
Kellystown Co. v. Hogan [1985] I.L.R.M. 200	Interpret statutory words to produce workable result.	Reference point for workable interpretation principle.
McGowan v. An Coimisiún Pleanála [2025] IEHC 405	Discretionary power should not be construed to impose unworkable obligations.	Used to caution against onerous readings of discretionary powers.
An Taisce v. An Bord Pleanála (Kilkenny Cheese) [2022] IESC 8	EIA obligations should not impose impossibly onerous requirements.	Applied to resist arguments seeking impossible standards for EIA/AA.
Concerned Residents of Treascon and Clondoolusk v. An Bord Pleanála [2024] IESC 28	Pleading standards and limits on relief without pleaded grounds.	Relied on to emphasise strict pleading and limiting relief to pleaded case.
Sweetman v. An Bord Pleanála (Sweetman XV) [2020] IEHC 39	EU law transposition and pleading particularity.	Cited to stress clarity needed for EU transposition/non‑transposition claims.
Rushe v. An Bord Pleanála [2020] IEHC 122	Pleading of EU law points requires particularity.	Used to support requirement of specificity for EU law pleadings.
Alen‑Buckley v. An Bord Pleanála [2017] IEHC 311	Non‑transposition claims must be properly pleaded.	Cited to reject unpleaded non‑transposition claims.
Ballyboden Tidy Towns Group v. An Bord Pleanála [2022] IEHC 7	Pleading rules are strict; scattergun pleadings are inappropriate.	Applied to criticise scattergun or imprecise pleadings in planning judicial review.
Reid v. An Bord Pleanála (No. 7) [2024] IEHC 27	Applicants are confined to their pleadings; need for route‑map linking facts to relief.	Adopted as central to assessing the Applicant's pleadings and scope of permitted relief.
Ballyboden Tidy Towns v. An Bord Pleanála [2021] IEHC 648	Recital of high‑level principles insufficient; must provide route‑map.	Used to require Applicants to link specific factual problems to relief sought.
Foley v. Environmental Protection Agency [2022] IEHC 470	Need for route‑map connecting facts to relief; clarity in pleadings.	Reinforced pleading requirements for complex regulatory/EU issues.
Stapleton v. An Bord Pleanála & Savona [2024] IEHC 3	Complex EU law points must be properly pleaded and particularised.	Applied when considering whether Applicant had pleaded necessary particulars.
Hellfire Massy Residents Association v. An Bord Pleanála [2022] IESC 38	Scattergun pleadings are unacceptable.	Used to criticise broad or unfocused pleadings.
Babington v. Minister for Justice & Ors. [2012] IESC 65	Pleading requirements and danger of repetitive reformulations.	Cited to encourage concise and focused pleadings.
Hayes v. Environmental Protection Agency [2024] IECA 162	Timely marshaling of evidence; limits on late evidence.	Invoked to reject late‑filed evidence not properly explained.
Sliabh Luachra v. An Bord Pleanála [2019] IEHC 888	Affidavit evidence can be excluded where there has been unexplained delay causing prejudice.	Applied to exclude or discount late affidavit material.
Kennedy v. An Bord Pleanála [2024] IEHC 570	Limits on replying affidavits; inadmissibility of late ex post facto evidence.	Relied on to exclude Affiant 4's late affidavit as improper reply/evidence.
Oxigen Environmental v. An Coimisiún Pleanála [2025] IEHC 632	Affidavits must not rewind the clock to adduce evidence that was reasonably available originally.	Used to support exclusion of late evidence and to emphasise case management rules.
Fahybeg Windfarm Opposition Group v. An Bord Pleanála [2025] IEHC 310	Late expert evidence and inadmissibility concerns.	Referenced when rejecting late attempts to adduce expert material.
RAS Medical Ltd v. Royal College of Surgeons in Ireland [2019] IESC 4	Where conflicts of admissible evidence exist absent cross‑examination, resolve against party bearing onus.	Cited in relation to evidential burden and assessment of affidavit conflicts.
Re Bayview Hotel (Waterville) [2022] IEHC 516	Expert evidence is an area where the court is not automatically obliged to accept material absent cross‑examination.	Used to caution against accepting untested expert assertions.
Doorly v. Corrigan [2022] IECA 6	Court may evaluate inherent defects in evidence.	Applied to highlight court's fact‑finding and assessment powers.
DPP v. Barnes [2006] IECCA 165	Court not constrained to accept the only account available; can prefer some evidence over other evidence.	Invoked to support critical evaluation of affidavits.
Tesco Ireland Ltd v. Stateline Transport Ltd [2024] IECA 46	Court's approach to expert evidence and credibility where cross‑examination is absent.	Referenced in evidential discussion relating to expert affidavit weight.
Carrownagowan Concern Group v. An Bord Pleanála [2024] IEHC 300; [2025] IESCDET 9	Doctrine of harmless error and onus shifting where error is demonstrated.	Cited extensively in relation to harmless error doctrine and use of developer/state evidence to exclude reasonable possibility of different outcome.
Eco Advocacy CLG v. An Bord Pleanála [2023] IEHC 713; [2025] IEHC 15	Applicants must displace decision‑maker's conclusion evidentially; harmless error principles.	Used in explaining requirement that applicants must show scientific doubt by evidence.
Nagle View Turbine Aware Group v. An Bord Pleanála [2024] IEHC 603	Applicant bears burden to show scientific/factual shortcomings in EIA/AA.	Applied to stress evidential burden on Applicant concerning AA/EIA deficiencies.
Minoa Ltd v. An Bord Pleanála [2024] IEHC 704	Evidential standards for environmental challenges.	Referenced to reinforce evidential expectations on applicants.
Ó Murthuile v. An Bord Pleanála [2025] IEHC 498	Evidential approach in AA/EIA challenges.	Used in the survey of authorities on evidential burden.
Roache v. An Bord Pleanála [2024] IEHC 311	Evidential standards in environmental judicial review.	Referenced to support reliance on material before decision‑maker at time of decision.
Ryanair DAC v. An Bord Pleanála [2025] IEHC 74	Recent authority on standards of review in planning context.	Included among contemporary authorities cited for AA/EIA principles.
Donegal County Council v. Planree [2024] IECA 300	Evidential requirements and application of EU environmental law.	Used to illustrate evidential approach in environmental judicial review.
Massey v. An Bord Pleanála (No. 2) [2025] IEHC 206	Application of harmless error doctrine; evidential burden.	Quoted on harmlessness and use of developer evidence to show no effect on outcome.
An Taisce v. An Bord Pleanála (No. 2) [2021] IEHC 422	Where flaws exist in assessments they must be demonstrated evidentially.	Cited to support that AA/EIA inadequacies must be demonstrated by applicant evidence.
Commission v Ireland (C‑50/09) ECLI:EU:C:2011:109	Standard of assessment: EIA must be as complete as possible.	Used to summarise EU law standard for EIA/AA.
R (Edwards) v. Environment Agency [2008] UKHL 22	European assessments are iterative; flaws can be addressed later in process.	Cited in discussing iterative nature of EIA/AA processes.
Cogent Land LLP v. Rochford District Council [2012] EWHC 2542	Amendments to plans and iterative assessment principles.	Used to support that assessments can be developed during process.
No Adastral New Town Ltd v. Suffolk Coastal District Council [2015] EWCA Civ 88	Iterative assessment and practicalities of environmental assessment.	Invoked to support flexible approach to assessment process.
R (on the application of Finch) v. Surrey County Council [2024] UKSC 20	Deciding whether an effect is "significant" requires value judgment; different decision‑makers may reach different conclusions.	Applied to underline evaluative character of significance assessments.
Holohan v An Bord Pleanála (C‑461/17) ECLI:EU:C:2018:883	Standards for AA and interpretation of "reasonable scientific doubt".	Cited in explaining that absence of reasonable doubt does not require absolute certainty.
R (Mynydd Y Gwynt Ltd) v. Secretary of State [2016] EWHC 2581	Relevant to standards for habitat/bird collision risk assessment.	Referenced when discussing methodological standards for collision risk evidence.
Landelijke Vereniging tot Behoud van de Waddenzee v Staatssecretaris (Waddenzee) C‑127/02 ECLI:EU:C:2004:482	Principles on reasonable scientific doubt and standard of proof in AA context.	Used to explain meaning of absence of reasonable scientific doubt and evidential approach.
Gemeinde Altrip v Land Rheinland‑Pfalz (C‑72/12) ECLI:EU:C:2013:712	Doctrine that not every procedural defect requires quashing; harmless error doctrine in EIA context.	Applied to support the court's ability to find an error harmless relying on developer/state evidence.
R (Champion) v. North Norfolk District Council [2015] UKSC 52	Harmless error and ability of courts to rely on evidence to exclude possibility of different outcome.	Used to justify reliance on developer/state evidence to demonstrate harmlessness of procedural defects.
Canterbury City Council v. Secretary of State [2019] EWHC 1211	Harmless error doctrine in planning/EIA context.	Cited in support of harmless error reasoning.
R. (Hudson) v. Windsor and Maidenhead [2021] EWCA Civ 592	Harmless error and discretion not to quash where defect would not affect outcome.	Referenced in harmless error discussion.
Commission v Ireland (Derrybrien) C‑261/18 ECLI:EU:C:2019:955	Judgment on remedial approach where EU law breach would have material effect; remedial norms.	Cited to note that after‑the‑event assessments should be exceptional where EU law breach would materially affect outcome.
Independent Newspapers v. I.A. [2020] IECA 19	Discretion as to remedies for domestic law breaches.	Used to explain court's broader discretion when determining remedy for domestic law errors.
De Róiste v. Minister for Defence [2001] IESC 4	Discretionary nature of judicial review at leave stage.	Cited to show discretion applies also at leave stage.
O'Connell v. Behan [2021] IECA 186	Relevant factors in exercise of discretion (including applicant conduct, prejudice, triviality).	Applied in weighing proportionality and discretion over remedy.
Ballyboden Tidy Towns Group v. An Bord Pleanála [2024] IESC 4	Court's discretion and power to grant unpleaded relief only within contours of pleaded case.	Referred to when limiting relief to pleaded grounds.
Walton v. Scottish Ministers [2013] UKSC 44	Harmless error doctrine in environmental law.	Used to support harmlessness analysis in environmental review.
UH v An tAire Talmhaíochta (C‑64/20) ECLI:EU:C:2021:14 (AG Bobek opinion)	Procedural/AA jurisprudence referenced for remedial principles.	Invoked in the wider EU law context of harmless error and remedies.
Coöperatie Mobilisation for the Environment UA v College van GS (C‑293/17 & C‑294/17) ECLI:EU:C:2018:882	Role of national courts in in‑depth examination of scientific soundness of AA.	Cited to indicate national courts have responsibility to examine scientific soundness of AA.
Heather Hill Management Company CLG v. An Bord Pleanála [2022] IEHC 146	Harmless error and standards for AA/EIA—absence of reasonable doubt not absolute certainty.	Referenced in discussion of standards for AA and harmlessness.
M.R. (Bangladesh) v. International Protection Appeals Tribunal [2020] IEHC 41	Read decisions in a way that makes sense; avoid fishing for technicalities.	Applied when construing Company B's decision sensibly.
R. (on the application of Champion) v. North Norfolk District Council [2015] UKSC 52	(repeat) See above re harmless error and evidential reliance.	See above entries; used in harmless error discussion.
Other authorities cited in the judgment (various domestic and EU decisions)	Support for principles: pleading rigour, onus of proof, reading decisions in context, admissibility of late evidence, harmless error, discretion and standards for AA/EIA.	The court relied on the body of case law collectively to frame a structured analytical approach (the eight‑fold test and its constituent principles) and to decide admissibility, evidential burden and discretionary remedy issues in this case.

Court's Reasoning and Analysis

The court structured its analysis by reference to an eight‑fold framework distilled from authority (jurisdictional requirements; legal correctness and workability; pleading adequacy; standing; material before the decision‑maker; onus of proof; harmless error; and discretion). The court then applied those principles to the facts and procedural history.

Key steps in the court's reasoning:

• Admissibility of late evidence: The court found the late affidavit filed by Affiant 4 (sworn 12 November 2025) to be, in large part, inadmissible or of no weight because it introduced ex post facto matters, was not a true replying affidavit, and the Applicant had failed to marshal such evidence at the appropriate procedural stage. Authorities on lateness and replying affidavits (including Oxigen and Kennedy) were followed.
• Pleadings and route‑map: The Applicant was held to be confined to its pleaded case. The court found several pleas to be inadequately particularised and lacking the necessary route‑map connecting alleged errors to the relief sought. The court emphasised the strict pleading requirements for complex EU law complaints.
• Onus of proof and evidence in AA/EIA challenges: The court reiterated that, save in defined exceptions, the onus is on the applicant to demonstrate inadequacy of AA/EIA (usually by admissible expert evidence or by showing a patent flaw on the face of the materials). Applying this, the court found the Applicant had not discharged the onus in relation to claims of scientific doubt or inadequacy concerning the SPAs and species at issue.
• Workability and standards: The court applied the workability principle to reject arguments that Company B should have constantly updated or autonomously applied foreign technical guidance (the NatureScot guidance) as a binding standard; the court noted such an approach would be unworkable absent prominence and acceptance of new standards.
• Irish language ground: The court accepted that bilingual policies exist but held that the absence of simultaneous Irish publication was an oversight rectified by subsequent publication (9 July 2025). The court concluded there was no legal breach that would justify certiorari; if any breach existed, it was harmless and discretionary considerations (including the climate/public interest context and lack of prejudice) weighed against quashing.
• Conservation objectives and measures (State concession): The State conceded that site‑specific conservation objectives for the Gearagh SPA were published only on 25 April 2025 (after the decision). The court ordered, by consent, a declaration to that effect. However, the court found that other complaints about absence of conservation measures or failure to consider non‑qualifying species significantly present were not established evidentially by the Applicant.
• Appropriate Assessment: On the substantive AA complaints (core ground 3), the court held that the materials before Company B, including the NIS, EIAR, further information and the Commission's ecologist and environmental scientist reports, enabled Company B to conclude there was no reasonable scientific doubt. The Applicant's post hoc assertions were insufficient to overturn that conclusion. Points concerning particular species (Hen Harrier, Merlin, Golden Plover) were rejected for lack of admissible evidence and because the decision‑maker had reasonably addressed those items on the material before it.
• EIA issues and turbine relocation condition: Core ground 4 was largely withdrawn. The remaining point concerning the minor relocation of Turbine T7 was inadequately pleaded and, in any event, the court found no established defect in the EIA or Company B's exercise of its conditioning power; the expert/material basis for an asserted landslide risk was not advanced by admissible evidence.
• Harmless error and discretion: The court applied the harmless error doctrine from EU and domestic jurisprudence (including Altrip and related authority) and concluded that any procedural or technical shortcomings alleged by the Applicant were either rectified, immaterial, or would be disproportionate to remedy by certiorari. The court emphasised that, where an error is shown, the onus shifts to the opposing parties to demonstrate harmlessness; Company B and the developer provided evidence sufficient for the court to conclude no reasonable possibility existed that the outcome would have been different.

Holding and Implications

HOLDING:

(i) By consent, a declaration was made that until 25 April 2025 the State respondents had not put in place site‑specific conservation objectives for the Gearagh SPA (the declaration was accepted by the State).

(ii) The proceedings were otherwise dismissed in Module I: core ground 1 (Irish language) was dismissed; core ground 2 was withdrawn; the bulk of core ground 3 (AA) and core ground 4 (EIA) were dismissed on evidential, pleading and admissibility grounds save insofar as further issues remain to be addressed in relation to a previously modularised "Power" issue; core ground 5 was dealt with by the consent declaration and the balance dismissed; core ground 6 was dismissed as academic in light of the court's disposition.

Implications:

• Direct effect: The planning decision of Company B stands; only a limited declaratory concession regarding the timing of publication of the Gearagh SPA SSCOs was recorded. The Applicant's wider challenge did not result in quashing the permission in Module I.
• Evidence and procedure: The judgment emphasises strict adherence to case management, timely presentation of evidence (especially expert evidence) and the requirement for clear pleadings linking facts to relief in judicial review, especially in environmental/EU law contexts.
• Harmless error and discretion: The court reaffirmed that not every procedural or technical error requires quashing; courts may rely on material from developers or State parties to exclude a reasonable possibility that an error affected outcome, and they retain discretion to refuse certiorari where disproportionate.
• No new legal principle: The court applied existing doctrines (pleading rigour, onus of proof, harmless error, deference on evaluative judgments and procedural admissibility). The judgment clarifies application of those doctrines in the specific factual matrix but does not purport to establish novel legal rules beyond the application of existing authority.

Order

• A declaration (by consent) was made regarding absence of Gearagh SPA SSCOs until 25 April 2025.
• The proceedings were otherwise dismissed in Module I (subject to reserved issues in relation to a modularised "Power" issue and related standing question to be addressed in a further module).
• Costs: the court made provisional cost directions (some costs reserved) and preserved certain cost questions for written submissions.
• Case management: the matter was listed for mention and perfection of the order was postponed pending outcome of the final module.

Notes on Anonymisation and Source

All references to parties, bodies and individuals in this summary have been anonymised and rendered in neutral placeholders consistent with the source text and the requirement to avoid use of personally identifying information. The summary was prepared strictly from the content of the provided judgment text and does not add factual material beyond that judgment.