Summary of High Court Opinion (Leave to Appeal) — Judge Humphreys

Factual and Procedural Background

This opinion concerns an application for leave to appeal from a judgment of the High Court upholding planning permission. The application for leave followed the substantive decision in which the High Court upheld the validity of a grant of planning permission (the substantive judgment is referred to as the principal judgment). The impugned planning decision was dated 3 December 2024; the proceedings were commenced on 4 February 2025; the principal judgment was delivered on 16 July 2025. The leave to appeal hearing was held on 6 October 2025 and a draft of this judgment was circulated to the parties on 21 October 2025.

The parties in the proceedings are anonymised in this summary as follows: the community group that brought the challenge is referred to as "Applicant"; the planning authority and governmental parties named in the record are referred to collectively as "Respondent"; and the developer/notice party is referred to as "Company A".

Company A's proposed development, as described in the evidence, comprised a retail store (gross floor area given in the record), associated car parking (297 spaces), ancillary facilities including a drive-through unit and a petrol filling station. Company A's affidavit (uncontradicted in the record) emphasised local economic benefits including an estimate of approximately 200 jobs and other local infrastructure benefits. The planning application was originally lodged on 16 January 2023 and included an Environmental Impact Assessment Report (EIAR), Appropriate Assessment screening report and related documentation.

Procedurally, following the substantive judgment dismissing the Applicant's challenge to the permission, the Applicant sought leave to appeal. The Applicant served written submissions dated 19 September 2025. The Respondent and Company A filed responses. The court requested clarification from the Applicant as to the precise procedural steps the Applicant contended should be followed by a decision-maker when assessing an emissions‑causing project. The court reserved judgment after the leave hearing and circulated a draft of this judgment to the parties for limited comments, none of which were made within the permitted seven‑day period.

Legal Issues Presented

1. Whether the Applicant should be granted leave to appeal from the High Court's substantive judgment upholding the planning permission.
2. Whether novel questions of law of alleged exceptional public importance were properly raised at the leave stage, specifically framed by the Applicant as:
1. Whether the planning authority has an obligation under the EIA Directive to identify, describe and assess transport‑related greenhouse gas (GHG) emissions and traffic increases cumulatively with other projects to determine significance having regard to the Climate Action Plan 2024 (CAP24).
2. Whether environmental effects inconsistent with matters listed in section 15(1)(a)–(e) of the Climate Action and Low Carbon Development Act 2015 are "significant" for the purposes of Article 1(2)(g)(iv) of the EIA Directive and whether the planning authority must carry out EIA by reference to those matters.
3. Whether, in projects prima facie inconsistent with the s.15(1)(a)–(e) matters, the planning authority must give specific reasons explaining how it performed its functions consistently with those matters.
3. Generally, whether the points the Applicant now seeks to raise were properly pleaded and argued at first instance so as to warrant leave to appeal.

Arguments of the Parties

Applicant's Arguments

• The Applicant asserted that the case raised questions of exceptional public importance suitable for appellate consideration and that the present case was complementary to a pending Supreme Court appeal in Coolglass.
• The Applicant proposed a detailed sequential procedure (presented in full to the court) which the Applicant contended the decision‑maker (the planning authority) should follow when considering "emissions‑causing" projects so as to comply with s.15 of the Climate Action and Low Carbon Development Act 2015 and EIA obligations. The core elements advanced by the Applicant included:
  • a requirement for developers to supply quantified estimates of net GHG emissions (including scope 3, net of mitigation and offsets) and supporting expert evidence;
  • an initial compatibility check against the applicable Climate Action Plan (CAP) and, if not CAP‑compatible, further evaluation against sectoral carbon budgets and national climate strategy and objective;
  • a presumption against granting permission for GHG‑emitting developments unless compatible with the CAP and other climate instruments, or unless it is practicable to refuse permission;
  • a requirement that the planning authority provide clear, publicly available reasoning demonstrating how its decision is consistent with s.15 matters, including cumulative assessment of emissions and justification where mitigation or offsets are relied upon.
• The Applicant characterised some of the legal questions as complementary to issues in other pending appellate litigation concerning the interpretation and application of the 2015 Act.

Respondent's Arguments

• The Respondent (planning authority and State parties) contended that the Applicant's new questions were not pleaded at first instance and were advanced only after the substantive judgment; consequently they could not properly be considered at the leave stage.
• The Respondent submitted that the Applicant attempted to convert a fact‑specific complaint about the adequacy of reasoning in the substantive decision into an abstract legal duty to benchmark transport emissions against national climate policy — a reformulation that was not pleaded and which the Respondent described as qualitatively different from the pleaded case.
• The Respondent noted that appellate authority on s.15 is forthcoming (the Supreme Court in Coolglass) and that the mere absence of prior appellate authority on a point does not alone establish uncertainty warranting certification for appeal.
• The Respondent emphasised general principles governing leave to appeal (including the requirement that points be properly raised at first instance and the public‑importance threshold) and relied on case law rejecting belated reprogramming of cases at the leave stage.

Notice Party (Company A) Arguments

• Company A submitted that the proposed questions were not pleaded and could not be retrofitted to the case; it characterised the Applicant's new formulations as an attempt to convert a fact‑specific adequacy complaint into an abstract legal duty not previously argued.
• Company A emphasised prejudice and public‑interest considerations: the project represented a significant local investment (including employment of circa 200 people), the planning application process had been ongoing for nearly three years, and prolonging the proceedings by allowing an appeal would cause unfairness and potential uncompensatable financial prejudice to Company A and third parties.
• Company A relied on its uncontradicted affidavit (sworn by Attorney Maguire) describing the development and its expected local economic benefits and noted the extensive documentation supplied with the planning application (including EIAR and appropriate assessment materials).

Table of Precedents Cited

Precedent	Rule or Principle Cited For	Application by the Court
Friends of Killymooney Lough v. An Coimisiún Pleanála (No. 1) [2025] IEHC 407	The substantive High Court judgment upholding the permission; background for the leave application.	Used as the principal judgment from which leave to appeal was sought; the present decision follows from and assesses the leave application in light of that substantive judgment.
Coolglass Wind Farm Limited v. An Bord Pleanála [2025] IEHC 1 (pending Supreme Court appeal)	Relevant to interpretation of the 2015 Act in respect of projects that assist emissions reduction; appellate clarification referred to.	The Applicant claimed the present case was complementary to Coolglass; the court held that the present case is not legitimately complementary in the manner alleged and that the Applicant only conceived that argument after the substantive judgment.
Massey v. An Bord Pleanála (No. 4) [2025] IEHC 309	General principles on leave to appeal (rehearsed elsewhere).	Referred to as setting out general principles applicable to leave to appeal; the court relied on the established framework from this line of authority.
O'Sullivan v. HSE [2023] IESC 11	Procedural remarks regarding draft judgments and the appropriate use of draft circulation.	Quoted to illustrate proper boundaries of draft judgment procedure and to caution parties against treating draft circulation as opening a new phase of litigation.
O'Sullivan v. Sea Fisheries Protection Authority [2017] IESC 75; [2017] 3 I.R. 751	Comment on fairness and procedural expectations in judicial proceedings.	Quoted for the proposition that parties should not assume that procedures resembling criminal trials are necessary in administrative judicial review contexts.
100 Meter Tall Group v. An Bord Pleanála [2025] IEHC 42	Authority on limits to expanding pleadings and the inadmissibility of raising new matters post‑pleading.	Used by analogy to reject the Applicant's attempt to raise new climate points not properly pleaded.
An Taisce v. An Bord Pleanála (Kilkenny Cheese) [2022] IESC 8	Rejection of "impossibly onerous and unworkable obligations" on decision‑makers.	The court held that the Applicant's first question (as formulated) was inconsistent with Kilkenny Cheese because it postulated an unworkable duty to assess all transport emissions in the State.
Connelly v. An Bord Pleanála [2018] IESC 31; [2021] 2 I.R. 752	Clarification of the law relating to reasons and considerations.	The court observed that clarification on the law of reasons has already been provided by the Supreme Court in Connelly, undermining the third question advanced by the Applicant as a basis for leave.
Concerned Residents of Treascon and Clondoolusk v. An Bord Pleanála & Ors [2024] IESC 28	Caution against sending under‑developed propositions to appellate courts; procedural prudence.	Quoted as an example of appellate reluctance to entertain half‑developed propositions; used to support refusal of leave as being in the public interest.
Carrownagowan (No.3) [2024] IEHC 549	On the limited significance of mere absence of appellate authority; leave criteria.	Relied upon to reject the Applicant's argument that the absence of appellate decisions on s.15 equates to legal uncertainty warranting leave.
Finch [2024] UKSC 20; Greenpeace Nordic (Case E‑18/24); Hassard et al [2025] NIKB 42	These foreign and EFTA decisions were cited by the Applicant as comparative authority about climate/EIA questions.	The court (and Respondent) treated these references as inapposite to the unworkable interpretation of the EIA Directive advanced by the Applicant and observed that citing such authorities did not resolve the fundamental pleading and factual deficiencies in the present case.
Fursey Maguire [2023] IESCDET 96; Phoenix Rock [2023] IESCDET 97	Authority illustrating that absence of appellate precedent alone is insufficient to establish uncertainty warranting leave.	Referred to in support of the proposition that lack of appellate decisions does not per se justify certification for appeal.

Court's Reasoning and Analysis

The court's analysis focused principally on whether the new issues the Applicant sought to raise at the leave stage were properly part of the case such that appellate consideration was appropriate. The court applied established principles for leave to appeal and proceeded through the following reasoning steps, based exclusively on the material in the opinion:

1. Preliminary constitutional and jurisdictional observation: An appellate court should not be asked to decide points that were neither pleaded, evidenced, argued nor decided at first instance because doing so would effectively make the appellate court a court of first instance and would be constitutionally improper.
2. Timing and genesis of new points: The court observed that the Applicant's elaborate climate law formulation emerged only after the substantive judgment was delivered and thus constituted a belated reprogramming of the case. The court described the Applicant's claimed "Eureka" moment about a complementary s.15 duty as arising post‑judgment rather than being part of the pleaded case.
3. Evaluation of the Applicant's proposed questions: The court considered each of the Applicant's three framed questions. It concluded:
   • Question 1 (cumulative assessment of transport GHGs benchmarked to CAP24) was not pleaded; the pleaded grounds had been a fact‑specific complaint about lack of regard to CAP24, not an argument that the planning authority had a legal duty to undertake a State‑wide cumulative transport emissions assessment. The court found the Applicant's formulation to be qualitatively different and unworkable.
   • Questions 2 and 3 (significance under the EIA Directive with reference to s.15 matters; and the content of reasons required under s.15) were also not advanced or pleaded at first instance and therefore could not properly be entertained on a leave application. The court noted that the Applicant's pleadings on s.15 were limited to a technical claim that the board did not consider the latest plan, which did not cover the broader legal points now advanced.
4. On the proper treatment of "emissions‑causing" projects the court recorded, based on the Applicant's submissions and the court's own provisional identification, three essential steps that might be involved in assessing an emissions‑causing project in an appropriate case:
   1. Identification of net emissions (including scope 3 and net of mitigation/off‑sets) compared with a counterfactual baseline;
   2. Evaluation against available national and sectoral targets/headroom;
   3. Evaluation of practicability of compliance where there is excess (e.g., justification based on imperative needs).
   However, the court emphasised that these formulations were provisional and that the Applicant had not pleaded them as part of its case at first instance and therefore they could not properly be the basis for leave here.
5. Assessment of whether the points were matters of law and of public importance: The court assumed arguendo that the hypothetical points could be legal questions, but stressed that inventing new points of law after an adverse judgment is not a legitimate basis for leave. The court applied the public‑importance threshold and concluded the Applicant failed to establish that the points, as now formulated, both properly arose and were of exceptional public importance in this case.
6. Consideration of precedent and alleged uncertainty: The court rejected the Applicant's attempt to establish uncertainty by citing various domestic and foreign authorities. It emphasised that the mere absence of appellate decisions on a point does not automatically justify certification and invoked prior authorities to that effect.
7. Public‑interest and prejudice factors: The court found allowing leave would not be in the public interest given the limited emissions implicated by this project, the potential prejudice and delay to Company A and third parties (including local employment), and the fact the project and associated litigation had been ongoing for several years. The court noted the uncontradicted affidavit of Company A's representative emphasising local economic benefits and the extensive documentation filed at the planning stage.
8. Conclusion on whether points properly arose: Because the Applicant's new submissions were not pleaded, evidenced or argued at first instance, the court concluded the points did not properly arise for adjudication on a leave application and therefore leave should be refused.

Holding and Implications

Holding: The court ordered that the application for leave to appeal is dismissed.

Implications and consequences:

• The dismissal means that the substantive High Court judgment upholding the planning permission stands and will be perfected as the final order of the High Court in these proceedings.
• The court directed that, if an application for leapfrog leave to the Supreme Court is made and the Supreme Court accedes to it, the costs of the leave to appeal application are to be costs in that appeal; otherwise there is to be no order as to costs for the leave application.
• The court emphasised that the present case is not an appropriate vehicle for developing the broad set of climate law propositions urged by the Applicant due to pleading deficiencies, the limited factual emissions at issue, and the public‑interest and prejudice considerations associated with prolonging the project's process.
• No new precedent on the substantive content of s.15 obligations or detailed EIA obligations in the climate context was established by this leave decision; the court refused leave principally on procedural and public‑interest grounds rather than by resolving the novel conceptual questions posed by the Applicant.

Final Order (as stated in the opinion)

1. The application for leave to appeal is dismissed.
2. If an application for leapfrog leave to the Supreme Court is made and acceded to by the Supreme Court, the costs of the leave to appeal application are to be treated as costs in that appeal.
3. Otherwise, there shall be no order as to costs in respect of the leave to appeal application.
4. The order made in the substantive judgment is to be perfected forthwith as the final order of the High Court in the proceedings with no further listing.

Notes on Scope and Sources

This summary is confined strictly to material expressly contained in the provided opinion and does not invent or infer facts, arguments or legal holdings beyond those recorded in the opinion. Where the opinion described a party's extensive written submission verbatim or at length (notably the Applicant's proposed procedural steps for emissions‑causing projects), the court recorded that material and treated it as illustrative of the Applicant's position; the court nonetheless declined to adopt those formulations for the purposes of granting leave because they were not pleaded at first instance.