Pre‑Application Planning Advice Is Not a Justiciable Decision: Millar v South Ayrshire Council [2025] CSOH 35

Introduction

This judgment from the Outer House of the Court of Session (Lord Richardson) addresses a recurring but under‑litigated question in Scottish planning law: does an officer’s pre‑application advice letter have legal effect capable of judicial review? The petitioners—six proprietors of residential units within the historic and Category A listed Coodham House, South Ayrshire—sought to reduce a Supervisory Planner’s pre‑application advice letter (9 February 2024) to a developer (Hallbar Homes), which stated that a 2004 planning permission (ref. 02/00790/FUL) for a substantial estate development “remains extant by virtue of works to Coodham House having commenced.”

The petitioners contended that the letter was a standalone “decision” with immediate legal effects—capable of triggering development inconsistent with the development plan and diminishing the value of their properties—and that it was unlawful because (i) there had been no lawful commencement (due to unmet pre‑commencement conditions: the Whitley principle) and (ii) the permission had become incapable of implementation (Hillside Parks).

The respondent Council argued that the letter, expressly caveated as pre‑application advice, was not a justiciable decision, created no legitimate expectation, and did not affect legal rights. It also argued that, even if reviewable, the petitioners had not shown an error of law or irrationality.

Summary of the Judgment

Lord Richardson refused the petition. The court held that:

The 9 February 2024 pre‑application advice letter is not a justiciable “decision.” It has no legal effect, does not bind the authority, and cannot be treated as an extra‑statutory certificate of lawfulness (Town and Country Planning (Scotland) Act 1997, ss 150–151). It is incapable of founding legitimate expectations (Re Finucane).
The proper statutory route for determining the lawful status of development is via certificate procedures, not via reliance on officer correspondence (Reprotech).
Even if the letter were justiciable, the respondent’s view that the 2004 permission was extant was not shown to be legally erroneous or irrational. The court endorsed a flexible, context‑sensitive approach to the Whitley principle (Hart Aggregates; Greyfort; Hammerton), recognising that where enforcement is time‑barred or would be unlawful/irrational, past works may still amount to effective commencement.
The petitioners’ “implementation” argument (Hillside Parks) failed because the letter said nothing about whether the 2004 permission could still be implemented; it merely expressed a view on extant status.

Result: Petition refused; expenses reserved.

Background and Procedural Context

Coodham House (built 1831) is a Category A listed building. In March 2004 the respondent granted permission (02/00790/FUL) for: conversion/extension of the House to 12 units; 41 houses in the grounds; access roads; and associated works—the classic model of “enabling development” to fund restoration of a heritage asset. The permission had numerous pre‑commencement and other conditions.

A separate 2005 permission (04/01015/FUL) authorised a different House scheme (9 units and other adjustments), without pre‑commencement conditions, under which works were undertaken between 2005 and 2009 and the nine units sold. Several later permissions in 2009–2011 for houses in the grounds were granted (some lapsed; three units permitted in 2011, two built, one part‑built).

In 2023 Hallbar Homes made a pre‑application enquiry. The Supervisory Planner’s letter (9 February 2024) stated the 2004 permission “remains extant” by virtue of commencement at the House and called that extant permission a “significant material consideration,” but expressly caveated the advice as officer‑level, pre‑application, and without prejudice to any future decision. When the petitioners challenged the basis for saying the 2004 permission remained extant, the same officer replied (3 May 2024) that “the Planning Authority maintains its view” after reviewing planning history and case law.

Issues

Whether the 9 February 2024 pre‑application advice letter contained a justiciable “decision” susceptible to judicial review.
If so, whether the Council’s view that the 2004 permission remained extant was unlawful because:
- (a) there was no “lawful commencement” given alleged non‑compliance with pre‑commencement conditions (Whitley principle); and/or
- (b) the permission had become incapable of implementation due to the physical alterations implemented under later permissions (Hillside Parks).

Analysis

1) Precedents and Statutory Framework

Reprotech Ltd v East Sussex CC [2003] 1 WLR 348 (HL): A central authority for the proposition that informal officer statements cannot substitute for a statutory process (there, s64 TCPA 1990; in Scotland, ss 150–151 of the 1997 Act). Lord Richardson relies on Reprotech to reject the attempt to treat the pre‑application letter as an extra‑statutory certificate of lawfulness.
Re Finucane’s Application [2019] HRLR 7 (UKSC): Legitimate expectations require a promise “clear, unambiguous, and devoid of relevant qualification.” The court finds the letter plainly fails this standard (it is expressly caveated as non‑binding advice).
Elmford Ltd v City of Glasgow Council (No 2) 2001 SC 267; Wightman v Secretary of State for Exiting the EU 2019 SC 111: Petitioners invoked these to argue against undue formalism in identifying a reviewable decision. The court distinguishes: unlike Elmford, the letter here had no legal effect; Wightman’s warning against “procedural niceties” does not displace the statutory and procedural context.
Mansell v Tonbridge and Malling BC [2017] EWCA Civ 1314; R (Campaign Against Arms Trade) v Secretary of State for International Trade [2019] EWCA Civ 1020: Reinforce that judicial review is not a merits appeal; review is for error of law or irrationality. The court approaches the petitioners’ grounds through this lens.
Town and Country Planning (Scotland) Act 1997:
- Section 27: when development is “begun” (low factual threshold).
- Section 58: time limit for commencements (here: five years).
- Sections 123–124: breach of control (distinguishing development without permission and breach of condition) and time limits for enforcement.
- Sections 150–151: certificates of lawfulness (existing and proposed). The court emphasises these as the proper route to determine lawfulness.
William Grant & Sons Distillers Ltd v Moray Council 2018 SLT 525: Confirms the threshold for commencement is “very low” (petitioners accepted this).
Whitley & Sons v Secretary of State for Wales (1992) 64 P&CR 296: The “Whitley principle”—non‑compliance with a condition precedent means development is not lawfully commenced. This principle underpins the petitioners’ core argument.
Trump International Golf Club Scotland Ltd v Scottish Ministers [2015] UKSC 74: Conditions in public documents are interpreted objectively in context. The court accepts that the “prior to commencement” conditions read as conditions precedent, but moves on to the more nuanced Hart/Greyfort approach to whether they “go to the heart” of the permission.
R (Hart Aggregates) v Hartlepool BC [2005] EWHC 840 (Admin); Greyfort Properties Ltd v SSCLG [2010] EWHC 3455 (Admin); [2011] EWCA Civ —: Hart cautions against rigid application of Whitley, drawing a distinction between formal “conditions precedent” and those which “go to the heart” of the permission; failures on some conditions may be mere breaches enforceable in the ordinary way, not fatal to commencement. The Court of Appeal in Greyfort approves the Hart approach and recognises exceptions to Whitley.
R (Hammerton) v London Underground Ltd [2002] EWHC 2307 (Admin): An important exception—where enforcement would be unlawful (e.g., time‑barred or irrational), development done in breach may nevertheless be effective to commence the permission. Greyfort acknowledges this exception.
Tesco Stores v Dundee City Council [2012] UKSC 13: While interpretation of policy is a question of law, the court underscores that assessing whether conditions “go to the heart” and broader planning judgments attract deference; only irrationality/perversity opens the door to intervention.
Hillside Parks Ltd v Snowdonia NPA [2022] 1 WLR 5077: A planning permission for a multi‑unit scheme is not generally severable; as the site is physically altered under other permissions, it may become physically impossible to carry out the approved scheme; departures must be material to stop further reliance. Here, crucially, the pre‑application letter never addressed implementability, so the argument failed at the threshold.
Robertson, petitioner [2022] CSOH 45: Supports the proposition that a later communication may constitute a separate decision; even if the February letter were reduced, the May email—treated as distinct—would not necessarily be affected.

2) The Court’s Legal Reasoning

(a) No justiciable “decision” and no legal effect

The February letter was:

Addressed to a developer concerning a pre‑application enquiry;
Expressly caveated as officer‑level, without prejudice to any future decision;
Issued outside the statutory certificate regime which exists precisely to answer questions of lawfulness.

Against that backdrop, the court held that treating the letter as a binding determination would improperly “elevate” it into an extra‑statutory certificate (Reprotech). The views stated did not—and were not intended to—alter legal rights or revive any lapsed permission. Any “effect” on the petitioners flows, if at all, from the 2004 permission itself, not from the letter. Nor could the letter found a legitimate expectation (Finucane): the promise lacked the required clarity and was heavily qualified.

(b) The alternative merits: why the Whitley challenge failed

Proceeding on the assumption that the letter was reviewable, the petitioners still failed. Lord Richardson recognised that several 2004 conditions used “prior to commencement” language and could be read as conditions precedent (Trump). But the court adopted the Hart/Greyfort perspective:

Whitley is a judicial construct to give effect to statutory purpose and should not be applied “unduly rigidly.”
Two recognised qualifiers applied:
- “Goes to the heart”: Whether a pre‑commencement condition is so fundamental that non‑compliance renders commencement unlawful is a matter of planning judgment. The court should be cautious before substituting its view for the authority’s (Greyfort). The petitioners did not demonstrate that the relevant conditions—e.g., a performance bond for landscaping—went to the heart of enabling development at Coodham in the manner they asserted.
- Enforcement impossibility/irrationality (Hammerton): Where, with the passage of time (see s124), enforcement is not lawfully possible, or would be irrational/abusive, works done in breach may nonetheless be effective to commence development. The petitioners provided no answer to the time‑bar and “irrational to enforce now” points referenced by the respondent and accepted by the court.
The factual threshold for “beginning” development was met by the House works (s27; William Grant). The petitioners’ argument that those works were “more consistent” with the 2005 permission did not advance matters: the two permissions were closely inter‑related, and there is no general principle that the same works cannot amount to commencement under more than one permission covering them.

(c) The Hillside implementation point

The court disposed of this briefly: the February letter did not opine on implementability at all; it only expressed a view on whether the 2004 permission remained extant. Even if reviewable, there was nothing to reduce on Hillside grounds because no “decision” had been made on that topic.

3) Impact and Significance

(i) The principled position on pre‑application advice

The judgment draws a bright line: pre‑application advice has no legal effect. It:

Cannot be relied upon as a decision;
Does not bind the planning authority or fetter later decision‑making;
Cannot found legitimate expectations;
Is no substitute for the certificate of lawfulness procedures in sections 150–151 of the 1997 Act (which carry procedural safeguards and a clear legal status).

This clarification should curb attempts to weaponise officer correspondence in litigation and will guide authorities to keep advice plainly labelled, caveated, and quarantined from formal determinations.

(ii) Commencement, conditions, and Whitley in Scotland

Although the Whitley analysis was, strictly, obiter, Lord Richardson’s reasoning is influential. The Outer House endorses the flexible English approach (Hart/Greyfort/Hammerton), recognising:

The need to distinguish textual “conditions precedent” from conditions that truly go to the heart of the permission;
The role of planning judgment in that assessment;
That enforcement time bars and public law constraints can render breaches irrelevant to the effectiveness of commencement.

This makes it harder, years later, to dismantle the extant status of a permission on the basis of alleged non‑compliance with pre‑commencement conditions where enforcement is time‑barred or would now be irrational.

(iii) Extant vs implementable under Hillside

The court reinforces a crucial distinction: a permission may be “extant” yet not (or not wholly) implementable due to later physical changes approved under different permissions (Hillside). Future disputes should avoid conflating these questions. If implementability is material, it must be squarely addressed in the decision or advice under challenge.

(iv) Procedural guidance for stakeholders

Developers should not treat pre‑application advice as a legal green light. Where the lawfulness of using an old permission matters (e.g., to avoid policy conflict), apply for a certificate of lawfulness.
Objectors/owners should recognise that challenges to pre‑application advice will fail; wait for a reviewable act (e.g., grant of planning permission, grant of certificate of lawfulness, enforcement decision) or seek declarator if appropriate.
Authorities should maintain robust protocols for pre‑application correspondence and signpost applicants to s150/s151 where status is in issue.

Complex Concepts Simplified

Pre‑application advice: Non‑binding officer views given before any application is lodged. It guides but does not determine outcomes; it does not change legal rights or the status of permissions.
Certificate of lawfulness (ss 150–151, 1997 Act): A statutory process to declare that a use or operation is (or would be) lawful. It carries legal effect and evidential weight. It is the correct vehicle to resolve “extant status.”
Commencement (s27): The factual act of beginning development; the threshold is low (e.g., digging foundations, substantive works on the authorised project).
Whitley principle: If pre‑commencement conditions that go to the heart of the permission are not met, development is not lawfully begun—so the permission can lapse. But courts apply this flexibly; some failures are merely breaches enforceable at the time, not fatal to commencement effectiveness years later.
Enforcement time limits (s124): Planning enforcement is time‑limited. Once time‑barred, breaches cannot be pursued; in that context, past irregularities may still count as effective commencement (Hammerton).
Legitimate expectation: A public law doctrine where a clear, unambiguous promise may bind a public authority. Heavily caveated, informal advice letters do not meet that standard (Finucane).
Hillside principle: A permission for a comprehensive scheme is generally not severable; if later development makes it physically impossible to complete the original scheme, further reliance on it may be curtailed. Minor, non‑material departures do not stop ongoing reliance.
Planning judgment vs legal interpretation: Courts interpret legal texts (permissions, conditions) as a matter of law, but defer to specialist planning judgment on evaluative matters (e.g., whether a condition “goes to the heart”).

Conclusion

Millar v South Ayrshire Council sets a clear Scottish precedent that pre‑application planning advice is not a “decision” and carries no legal effect. Parties seeking certainty on the lawfulness of development must use the statutory certificate regime; they cannot rely on officer correspondence to secure or attack legal status. The judgment also articulates, albeit obiter, a flexible approach to the Whitley principle in Scotland, aligned with Hart, Greyfort and Hammerton: whether pre‑commencement conditions are fatal to commencement depends on whether they truly go to the heart of the permission, on the planning judgment of the decision‑maker, and on enforcement realities and time bars.

Practically, the decision will:

Steer applicants and opponents toward the correct statutory mechanisms (ss 150–151) when “extant status” matters;
Limit the judicial reviewability of informal planning communications;
Encourage nuanced, context‑sensitive analysis of commencement and condition compliance; and
Remind parties not to conflate a permission’s extant status with its implementability under Hillside.

Key takeaway: in Scottish planning law, legal certainty about the status of a permission is obtained by formal decision‑making under statute—not by reliance on pre‑application advice. And if disputes arise years later, courts will be slow to unravel the effectiveness of commencement where enforcement is long past and public law fairness would be offended.