Supreme Court remits planning appeal to Commission to consider statutory duty to depart from development plan under 2015 Act.

AN CHÚIRT UACHTARACH

THE SUPREME COURT

O’Donnell C.J. Charleton J. O’Malley J. Woulfe J. Hogan J. Murray J.

[S:AP:IE:2025:000043

[2026] IESC 000

BETWEEN/

COOLGLASS WIND FARM LIMITED

RESPONDENT

AND

AN COIMISIÚN PLEANÁLA

APPELLANT

AND

IRELAND AND THE ATTORNEY GENERAL

NOTICE PARTIES

RULING of the COURT delivered the 2nd day of March 2026

1. This appeal came directly to this Court from the High Court pursuant to Article 34.5.4⁰ of the Constitution following the grant of leave by this Court on 16th May 2025: see [2025] IESCDET 65. The appeal was in respect of a decision of the High Court quashing a decision of An Coimisiún Pleanála (“the Commission”) which refused to grant the applicant, Coolglass Wind Farm Ltd. (“Coolglass”), planning permission in respect of a development of a 13-turbine windfarm and associated works in Timahoe, Co. Laois.

2. Judgment was delivered by the Court on 5th February 2026: see Coolglass Ltd. v. An Coimisiún Pleanála [2026] IESC 5. The Court is now called upon to rule (i) upon the issue of costs and (ii) the form of order. To that end the Court has had the benefit of written submissions filed by the parties and it considers that there is in the circumstances no need for an oral hearing on these issues.

The judgment of the Court

3. In its judgment the Court found that the Commission had erred in law in failing to address the implications of s. 15(1) of the Climate Action and Low Carbon Development Act 2015 (“the 2015 Act”) in the wake of important amendments made to that section which were effected by s. 17 of the Climate Action and Low Carbon Development (Amendment) Act 2021 (“the 2021 Act”). Specifically, this Court held that the Commission had erred in law in failing to consider whether s. 15(1) of the 2015 Act required it to consider departing from the terms of the Laois Development Plan and to exercise its powers under s. 37G(6) of the Planning and Development Act 2000 for this purpose. This was the principal issue before the Court (Core Ground 1) and it can be said that Coolglass unambiguously succeeded on this point.

4. This, however, was by no means the only issue before the Court. In the High Court the applicant had relied on six other grounds. Core Ground 2 had been adjourned by the High Court and Ground 6 was not pursued in this Court. Core Ground 3 related to a contention that the Commission had abdicated its functions under s. 15 of the 2015 Act to the Office of Planning Regulator and/or the Minister for Housing, Local Government and Heritage. Core Ground 4 concerned the proper scope of the Commission’s powers under s. 37(2) and s. 37G(6) of the Planning and Development Act 2000. Core Ground 5 involved a finding by the High Court that the State had violated the ECHR in reliance on the decision of the European Court of Human Rights in Verein KlimaSeniorinnen Schweiz v. Switzerland [2024] ECHR 304. Ground 7 related to a finding by the High Court that the State had violated EU law in failing to fulfil its duty of sincere co-operation.

5. In this Court, Coolglass did not seek to stand over the findings of the High Court in respect of either the ECHR (Core Ground 5) or the EU law ground (Core Ground 7), although it did, to some extent, nonetheless seek to rely on these points. These issues are addressed in the judgment of the Court and it is clear that Coolglass did not prevail in respect of either point. The Court also remarked (at paras. 154 and 155) that the manner in which Coolglass had actually engaged with the ECHR point was not altogether satisfactory. In particular, Coolglass had effectively asked the High Court to treat Article 8 ECHR as if it were a directly effective provision in Irish law and in its submissions to that Court it did not address the relevant corresponding provisions contained in Article 41 of the Constitution or, for that matter, the earlier decision of this Court in Friends of the Irish Environment CLG v. Government of Ireland [2020] IESC 49, [2021] 3 IR 1. In Friends of the Irish Environment this Court rejected the argument that there was, as such, a specific constitutional right to a clean environment.

6. While Coolglass failed in respect of Core Ground 3 (i.e., the abdication of functions argument), it prevailed in part in respect of Core Ground 4. We ruled that the Commission had, indeed, had regard to the wrong statutory provision of the 2000 Act and that it should have had regard to the powers given to it by s. 37G(6) of the 2000 Act (rather than the somewhat more restricted powers contained in s. 37(2)) to depart from the terms of the relevant Laois Development Plan. But we also held in the circumstances that this error was not fundamental or material to the validity of the decision. We also considered that, in any event, it had been induced in part by Coolglass itself, as in its submissions to the Commission it had made precisely the same error. We further indicated that we would not have quashed the Commission’s decision on this ground alone.

Coolglass was partially successful

7. Viewing Coolglass’s arguments as a whole, it may be said that it succeeded only in respect of Core Ground 1 in relation to the construction of s. 15 of the 2015 Act (as amended). This was, however, the single most important feature of the entire case. Two other grounds (Core Grounds 2 and 6) were not pursued before this Court. Coolglass failed in respect of Core Grounds 3, 5 and 7. Coolglass was partially successful in respect of Core Ground 4.

8. It cannot be said, accordingly, that Coolglass was “entirely successful” for the purposes of the costs provisions of s. 169(1) of the Legal Services Regulation Act 2015. While it is true that Coolglass succeeded on the most important aspect of the case, it is also the case that it in effect lost (or substantially lost) on the other four grounds which were still live for the purposes of the appeal. To that extent, the Commission also prevailed in substance in respect of the majority of these grounds.

9. In these circumstances, we consider that the justice of the appeal would be met by awarding Coolglass 50% of the costs of both the High Court proceedings and the Supreme Court appeal as against the Commission only, such costs to be adjudicated in default of agreement. This costs order reflects the fact that although Coolglass won on the most important point (Core Ground 1), it also lost in substance on the other live grounds, with a partial success only in respect of Core Ground 4. These further grounds added to the complexity and length of the appeal, including the number of case management meetings and the length of the written submissions.

The position of the Attorney General

10. The Attorney General was joined to these proceedings qua notice party, so that he was in effect acting as a form of amicus curiae. This is by now a fairly frequent occurrence, and this Court will often invite the Attorney to participate in this fashion in cases involving major questions that have significant implications for the public at large. This was one such case.

11. The standard order in such cases is that the Attorney abides his own costs. We see no reason to depart from that practice in the present case, so that there will be no order for costs either as against or in favour of the Attorney General.

The remittal order

12. The other remaining issue concerned the form of order in respect of remittal. All the parties were agreed that it was appropriate that the matter be remitted to the Commission in accordance with s. 50A(9A) of the 2000 Act. The Commission has indicated that it now proposes to appoint an inspector to prepare a supplemental report in which the precise issue indicated by the Court, namely, whether it should exercise its powers under s. 37G(6) of the 2000 Act in the light of s. 15(1) of the 2015 Act (as amended) can now be considered, together with any analysis of any up-to-date material.

13. We consider that we should accordingly make an order remitting the matter under s. 50A(9A) of the 2000 Act to the planning application process directly after the furnishing of the original Inspector’s Report and preceding the Commission’s decision. This will enable the Commission to arrange for a supplemental Inspector’s report addressing the question of whether the Commission should exercise its s. 37G(6) powers to depart from the terms of the Laois Development Plan in the light of s. 15(1) of the 2015 Act.

14. Coolglass agrees in general terms that this is the appropriate order which this Court should now make. It did, however, suggest that we should give specific directions to the Commission regarding the procedure now to be followed. We do not, however, propose to give any such directions. The Commission is a statutory body which is obliged to uphold the Constitution and the law. It must be presumed that the Commission will therefore abide by the principles of fair procedures in arriving at any decision in respect of the remitted matter.: see East Donegal Co-Operative Ltd. v. Attorney General [1970] IR 317.

Conclusions

15. It follows, therefore, that for the reasons stated the Court will: First, award Coolglass 50% of the costs of the High Court and the Supreme Court (to be adjudicated in default of agreement) as against the Commission, with no order for costs in respect of the Attorney General. Second, make an order under s. 50A(9A) of the 2000 Act remitting the matter to the planning application process directly after the furnishing of the original Inspector’s Report and immediately preceding the Commission’s decision so that the question of whether the Commission should exercise its powers under s. 37G(6) of the 2000 Act to depart from the terms of the Laois Development Plan in the light of s. 15(1) of the 2015 Act, can now be considered. The Commission will have liberty to appoint an Inspector to prepare a supplemental Report for this purpose.