Duty of Candour in Planning Judicial Review: No Compelled Affidavits of Commissioners’ Thought Processes Where the Statutory Record and Pleadings Put “Cards Face Up”

Case: Busher and Ors v An Coimisiun Pleanala and Anor (Approved) [2026] IEHC 362

Court: High Court of Ireland (Planning & Environment)

Judge: Ms Justice Emily Farrell

Date: 10 June 2026

1) Introduction

This judgment concerns an interlocutory application for directions in a statutory planning judicial review under ss. 50, 50A and 50B of the Planning and Development Act 2000 (as amended) (“PDA”). The applicants challenge a decision of An Coimisiún Pleanála (“the Commission”) dated 11 June 2025 granting Uisce Éireann permission for a wastewater treatment plant and associated works in Kilkee, Co. Clare (ABP-321258-24).

The immediate issue was novel in Irish planning JR practice: whether the Court should direct the Commission to provide a “full and candid account” (in substance, affidavits) of whether and how it considered certain disputed topics—odour, lighting and screening/landscaping—which underpin Core Grounds 1–3 of the substantive challenge.

The applicants argued that without compelled evidence of what was “in the mind” of the Commissioners, they would be unfairly hampered by the presumption of validity and the burden of proof in judicial review. The Commission and the notice party resisted the application, contending that the decision must be interpreted by reference to the written decision and the statutory planning record, and that compelling affidavits about internal deliberation would impermissibly invert the onus of proof.

2) Summary of the Judgment

  • The High Court refused the directions sought.
  • The Court held that, in this context, requiring affidavits detailing the Commissioners’ internal thought processes would effectively reverse the onus of proof and disapply the presumption of validity.
  • The Commission had not failed in its duty of candour: its Statement of Opposition identified, with specificity, the materials relied upon to meet the applicants’ case, and the statutory framework already requires openness (reasons and public file).
  • The applicants remain free at the substantive hearing to argue, by inference from the decision and record, that material matters were not considered or that reasons were inadequate, including by invoking the “main reasons on the main issues” requirement.
  • Delay was noted but would not have been determinative had entitlement been established.
  • No costs order was made at this stage given the accepted applicability of s. 50B PDA, with liberty to apply.

3) Analysis

3.1 The procedural and doctrinal setting: candour vs. presumption of validity

The judgment squarely addresses a tension that increasingly arises in environmental and planning litigation:

  • Duty of candour / transparency (“all the cards face upwards on the table”), associated with R v. Lancashire County Council, ex parte Huddleston [1986] 2 All ER 941 (“Huddleston”); and
  • Presumption of validity and the ordinary onus on the applicant to prove unlawfulness in judicial review.

Farrell J accepts the duty of candour as a governing principle, but emphasises that its content is context-sensitive: candour is aimed at ensuring justice can be done, not at transferring to the respondent the task of proving legality or supplying post hoc justifications.

3.2 Statutory openness in planning decisions was central

A key move in the Court’s reasoning is to distinguish the applicants’ position from the applicant in Huddleston. In planning, the PDA imposes built-in transparency:

  • s. 34(10) PDA: the Commission must state the main reasons and considerations for its decision (and for conditions);
  • s. 146(5) PDA: the file must be made available for public inspection.

Because the planning regime already externalises reasons and record, the Court treats the “cards on the table” obligation as being substantially satisfied through (i) the decision, (ii) the public planning file, and (iii) proper pleadings, unless some additional matter exists that cannot fairly be gleaned from those sources.

3.3 The Commission’s pleadings mattered: this was not “formulaic denial”

The applicants’ application was largely driven by litigation risk: recent cases where applicants failed to discharge the onus because they could not prove what was considered. Farrell J accepts the general concern but focuses on what the Commission actually did here.

The Commission’s Statement of Opposition pleaded that it would rely on the Inspector’s Report, the Commission’s Direction, Order, relevant documentation and policy documents—an approach aligning with Connelly v. An Bord Pleanála [2018] IESC 31, [2021] 2 I.R. 752, [2018] 2 I.L.R.M. 453 (decisions may be interpreted by reference to the materials before the decision-maker). The Court contrasts this with Elsharkawy v. The Minister for Transport [2024] IECA 258, [2025] 1 I.L.R.M. 162, where the respondent’s pleading failures were central to the candour critique.

Farrell J also places weight on the procedural architecture: Order 84 r. 22(4) requires verification of facts in the Statement of Opposition. The verifying affidavit here was sworn by an official not present at the decision. That did not count against the Commission because it was not attempting to introduce extra-record “mind evidence”; it relied on the written decision and file. The applicants, the Court held, were not entitled to compel affidavits in order to “bolster” the defence.

3.4 “Decision speaks for itself”: limits on going behind the record

The Court situates the application against a line of authority that restricts supplementation of reasons by affidavit:

  • State (Crowley) v. The Irish Land Commission [1951] IR 250: affidavits cannot add to, explain, or contradict the written order;
  • Tumblr Incorporated v. Coimisiún Na Meán [2024] IEHC 366 (with Jacksonway Properties v The Information Commissioner [2020] IEHC 73 and Utmost Paneurope DAC v Financial Services and Pensions Ombudsman [2020] IEHC 538): decisions ordinarily stand or fall on their own terms; subsequent elaboration is not permissible;
  • Friends of Killymooney Lough v. An Coimisiún Pleanála [2025] IEHC 407: ex post facto reasoning is generally impermissible.

Although the applicants disavowed seeking “ex post facto reasoning”, the Court treated the requested affidavits—what the Commissioners “actually considered”—as functionally similar in effect: it would invite evidence of internal deliberation to meet an onus that rests on the applicants, and thereby shift the litigation balance.

3.5 Presumption of validity and onus: the order would invert the burden

Farrell J restates, with extensive authority, that the onus in judicial review remains with the applicant, subject to limited exceptions not engaged here: Sherwin v. An Bord Pleanála [2023] IEHC 26; Amariei v. Chief Appeals Officer [2026] IESC 22; Rutledge v. Fingal County Council [2026] IEHC 223. The presumption of validity is reaffirmed by reference to In re Comhaltas Ceoltóirí Éireann (HC, 14 December 1977); Campus Oil v. Minister for Industry and Energy (No. 2) [1983] I.R. 88, [1984] I.L.R.M. 47; Grassridge v. Dun Laoghaire Rathdown County Council [2024] IEHC 669; Moran v. An Bord Pleanála [2025] IEHC 510.

The Court’s key doctrinal conclusion is explicit: the effect of the order sought would be to disapply the presumption. Applicants are entitled to attempt to rebut the presumption with direct or inferential evidence, but they are not entitled to compel the respondent to provide evidence proving validity merely because the applicants perceive themselves to be in an evidential difficulty.

The judgment also draws support from Ballyboden Tidy Towns Group v. An Bord Pleanála [2024] IESC 4, emphasising that validity and its presumption are not “within the gift” of the decision-maker, and are structurally relevant to who bears the burden of proof.

3.6 When might compelled affidavits be justified? A narrow opening

Although refusing relief, Farrell J identifies circumstances where an affidavit may be necessary to ensure fair conduct of the litigation:

  • where an inference cannot be drawn from the decision and record (e.g., an issue relating to the decision-maker’s expertise);
  • where the respondent relies on a matter not known to the applicant, as in Elsharkawy (including whether relied-upon advice existed in inspectable documentary form).

This is important: the judgment does not abolish candour-based procedural interventions; it confines them to cases where the record-based model cannot deliver fairness because the relevant information is genuinely outside what the applicant can access or infer.

3.7 Reasons, “main issues”, and inferential review: how applicants can still win

The applicants’ substantive complaints were that relevant matters were not considered and/or reasons were inadequate. Farrell J frames the proper route as orthodox reasons-based review: the applicants may seek to show invalidity by reading the decision as properly interpreted, including against the statutory duty to give reasons on the main issues.

On this theme, the Court references:

  • T.G. v. Refugee Appeals Tribunal [2007] IEHC 377: transparent consideration may be required depending on materiality;
  • Four Districts Woodland Habitat Group & Ors v. An Bord Pleanála & Ors [2023] IEHC 335 (via Coyne v. An Bord Pleanála [2023] IEHC 412): “having regard” does not necessarily require reasons for rejection, though main issues may independently require main reasons;
  • Cork County Council v. Minster for Housing, Local Government and Heritage & Ors [2021] IEHC 683: “having regard” implies looking at and factoring relevance/weight; references to an “enhanced duty” to give reasons in context;
  • Morehart v. An Bord Pleanála [2025] IEHC 418: absence of express reference does not, in every case, prove non-consideration; but a document of sufficient significance may have to be seen to have been considered (T.G.), while routine completeness is not required (Banzuzi v. Minister for Justice [2007] IEHC 2; A.W.S. v. Refugee Appeals Tribunal [2008] IEHC 276).

The practical upshot is a calibrated inferential approach:

  • High-materiality matters may require visible engagement (or at least reasons meeting the “main issues” obligation).
  • Lesser materiality matters need not be expressly mentioned: Wild Ireland Defence v. An Coimisiún Pleanála & Ors [2025] IEHC 726; Carrownagowan Concern Group v. An Bord Pleanála (No.2) [2024] IEHC 300.

Against that backdrop, the Court held that the applicants’ requested affidavits were not a legitimate shortcut around the ordinary inferential and interpretive tools available at the substantive hearing.

3.8 Precedents cited: how each shaped the outcome

  • R v. Lancashire County Council, ex parte Huddleston [1986] 2 All ER 941: source of the “cards face upwards” principle; however, planning’s statutory transparency distinguishes the present case, and Huddleston did not stand for a general right to compel affidavits of deliberation.
  • Reid v. An Bord Pleanála, [2021] IEHC 362 and Rogers v. An Coimisiún Pleanála [2026] IEHC 257: invoked by applicants as illustrations of evidential difficulty and matters “peculiarly within knowledge” of the Commission. Farrell J treats them as context-specific and not authority for a general entitlement to “mind evidence”.
  • Elsharkawy v. The Minister for Transport [2024] IECA 258, [2025] 1 I.L.R.M. 162: a modern restatement that candour remains important, but also tied to pleadings and fairness where the respondent relies on undisclosed matters. Distinguished because the Commission here identified record materials and did not attempt to shift to the applicants the burden of disproving undisclosed reasons.
  • O'Neill v. Governor of Castlerea Prison [2004] WJSC-SC 9109, [2004] 1 I.R. 298, [2004] 2 I.L.R.M. 241: confirms a respondent should disclose materials relevant to the impugned decision; used to underline the principle, but the Court finds compliance achieved via the planning record and pleadings.
  • RAS Medical Ltd v Royal College of Surgeons in Ireland [2019] IESC 4 and Student Transport Scheme Limited v. The Minister for Education and Skills [2021] IESC 35: reinforce transparency norms in public law litigation; consistent with, but not extending to, compelled affidavits of mental processes in this setting.
  • Concerned Residents of Treascon and Clondoolusk v An Bord Pleanála [2024] IESC 28: reminds that leave is permission to pursue pleaded grounds, not a roving inquiry—supporting resistance to procedural devices that expand judicial review into investigation.

3.9 Impact: what this changes (and what it does not)

(a) For planning JR practice

  • The judgment signals that directions compelling affidavits of Commissioners’ consideration will be exceptional, not routine.
  • Applicants cannot use “candour” as a mechanism to shift the evidential burden where the dispute is resolvable by interpreting the written decision and record.
  • Respondents can expect the Court to scrutinise whether pleadings are specific and record-based, aligning with Connelly and Order 84 pleading duties.

(b) For the duty of candour

  • Candour remains real, but its satisfaction may occur through statutory disclosure and proper pleadings, not necessarily through affidavit evidence from the actual decision-makers.
  • The duty does not entitle an applicant to compel internal deliberative evidence merely because proving unlawfulness is difficult.

(c) For future “missing consideration” claims

  • The case encourages litigants to focus on materiality: if a matter is central enough that the decision-maker “must be seen” to have considered it, the argument should be framed within the “main reasons on the main issues” jurisprudence (T.G.; Morehart), rather than as an attempt to interrogate decision-maker minds.
  • The judgment keeps open the possibility of compelled evidence where the decisive facts are outside the record and not inferable (the narrow category exemplified by Elsharkawy-type problems).

4) Complex Concepts Simplified

  • Duty of candour (“cards face up”): a public body must litigate transparently and not hide relevant materials. It is about fair process, not about proving the decision was lawful.
  • Presumption of validity: administrative decisions are assumed lawful unless the challenger shows otherwise. This allocates the burden of proof to the applicant.
  • “Decision speaks for itself”: courts generally assess legality based on the written decision and record; affidavits are not meant to add new reasons or retroactively clarify internal thinking.
  • “Main reasons on the main issues” (s. 34(10) PDA): the Commission must explain the principal reasons for its conclusion on the key issues. It need not address every detail, but it must provide enough to understand why the decision was made.
  • Inferential review: applicants can sometimes rebut the presumption of validity by showing that the absence of reference to a highly significant matter implies it was not considered (or that reasons are inadequate). Not every omission supports that inference.
  • Ex post facto reasoning: supplying new reasons after the fact to justify a decision; generally not permitted.

5) Conclusion

Farrell J’s decision in Busher and Ors v An Coimisiun Pleanala and Anor (Approved) [2026] IEHC 362 articulates a clear procedural principle for planning judicial review: the duty of candour does not, without more, justify compelling the Commission to file affidavits revealing Commissioners’ internal thought processes on whether particular issues were considered. Where the statutory planning framework provides a public record and a duty to give reasons, and where the respondent has identified the record materials relied on, a direction requiring “full and candid” accounts of mental deliberation would impermissibly invert the burden and undermine the presumption of validity.

The judgment therefore reinforces record-based judicial review in planning cases, while leaving a narrow path for additional evidence where a material issue is truly outside what can be inferred from the decision and file, or where the respondent relies on undisclosed matters in resisting the claim.