Executive Summary

On 14 October 2021, Ms Justice Costello in the Court of Appeal (COA) delivered her judgment in Heather Hill Management Company CLG and Anor v An Bord Pleanála [2021] IECA 259, overturning an earlier decision of the High Court. The COA considered the correct of interpretation of Section 50B of the Planning and Development Act 2000 (the 2000 Act). The COA determined that the protective costs order available under that section, for cases dealing with issues of national environmental law, will only apply to the issues and grounds of challenge that relate to environmental matters and not to others such as grounds relative purely to planning points.

High Court decision

Heather Hill Management Company CLG and Gabriel McGoldrick (the Applicants) successfully challenged a decision of An Bord Pleanala (the Board) to grant planning permission for a strategic housing development (SHD) of 197 dwellings in Galway. The challenge was made on a number of grounds, including the Habitats Directive, EU Flood Directive, material contravention of the Development Plan and landowner consent deficiencies. The Applicants argued that the entire proceedings attracted the special costs rules governing environmental litigation under Section 50B of the 2000 Act.

In the High Court, Mr Justice Simons adopted a literal interpretation of section 50B of the Act and held that the wording of Section 50B is such that costs protection applies to "proceedings" as a whole, rather than "grounds" raised. He set out his reasons for deviating from earlier High Court and CJEU decisions, and held that the Applicants were entitled to special costs protection in respect of all grounds raised, due to the environmental nature of the decision which was under challenge.

A link to our coverage of this case can be found here.

Court of Appeal decision

Statutory Interpretation of Section 50B

The COA considered that a consequence of the literal interpretation favoured in the High Court would mean the protective costs regime would even apply to cases where none of the grounds of challenge related to the environment, simply because the decision under challenge was made under legislation which gives effect to one of the specified environmental directives listed in Section 50B. The COA did not think this was the correct interpretation, stating that if the Oireachtas had intended to apply the special costs rules to all proceedings concerned with a decision involving environmental issues, it could have said so in the legislation.

The Court was bound to follow earlier judgments on the special costs rules

Giving the decision of the COA, Ms Justice Costello considered the case law on Section 50B and the High Court judge's divergence from it. She stressed that conflicting interpretations of statutory provisions are to be avoided if possible and the principle that prior judgments should be followed plays an important role. Ms Justice Costello could not agree with the High Court judge's observation that that doctrine applies with less rigour to the costs of environmental litigation.

Ms Justice Costello referred to the High Court judge's view that new decisions handed down by the CJEU weakened the precedent value of earlier judgments was 'overbroad'. This is not a reason to depart from decisions of national courts construing national legislation, unless the differing interpretation is required by reason of a decision of the CJEU. The High Court decision noted that restrictions on appealing decisions of the High Court relating to planning and environmental law meant that guidance from the appellate courts is not as common and as a result, High Court decisions could be more readily departed from by other High Court judges. Justice Costello said this did not justify a departure from following precedent.

Aarhus Convention

The COA stated that when a decision is challenged on the basis of national environmental law, Member State courts are obliged to interpret national procedural laws, to the fullest extent possible, in a manner consistent with the objectives set out in the Aarhus Convention. However, the COA held that where the application of national environmental law is not in issue i.e. where the court is invited, on classic grounds (for example that the decision was ultra vires) of judicial review, to quash a decision, then the "not prohibitively expensive" costs rule under the interpretive obligation to apply the Aarhus Convention to the widest extent possible would not apply.


The costs of litigation in the Superior Courts are governed by Order 99 of the Rules of Superior Courts and Section 169 of the Legal Services Regulation Act 2015. Where litigation relates to certain aspects of the environment, special costs protection under section 50B of the 2000 Act or under the Environment (Miscellaneous Provisions) Act 2011 is also possible. This decision only concerns the interpretation of Section 50B of the 2000 Act and reinstates the position that a protective costs order is available under Section 50B only to the issues and grounds of challenge which relate to certain environmental issues.

This issue had been considered by the High Court on at least seven different occasions, and also by the CJEU. This COA decision brings welcome clarity to the scope of environmental costs protection available under Section 50B.

A link to the full judgement can be found here.