Challenging an appeal decision in the High Court

A section 288 challenge asks whether an inspector made an error of law, and nothing else. It is not a second appeal on the planning merits, and the High Court will not substitute its own view about whether a scheme should have been permitted. Section 288 of the Town and Country Planning Act 1990 lets a person aggrieved apply to the High Court to question the validity of certain decisions, including appeal decisions, and the application must be made within six weeks. That six week period is a statutory time limit and the court has no general power to extend it.

Which sets up the real decision most clients face: whether an unsatisfactory decision letter contains a legal error at all, or whether it is simply a decision they dislike.

The difference between merits and legality

An inspector is entitled to reach a conclusion on planning judgement that another inspector would not reach. Weight is for the decision-maker. A decision letter that gives limited weight to a benefit you think deserved substantial weight is not, on that ground alone, unlawful.

What is reviewable is the process of reasoning and the legal framework applied. Did the inspector correctly interpret a policy, as opposed to applying it in a way you dislike. Did they take into account something legally irrelevant, or fail to take into account something they were obliged to consider. Did they give reasons adequate to let the parties understand why they won or lost on the principal issues. Did they act fairly.

The distinction between interpreting a policy and applying it is the one that generates most litigation. Interpretation is a question of law for the court. Application is a matter of planning judgement for the inspector. A great many grounds that look attractive in draft collapse once that line is drawn properly.

Grounds capable of founding a challenge

Inadequate reasons deserves a note of caution. The duty is to give reasons that are intelligible and adequate on the main issues, and the courts read decision letters as a whole, addressed to informed parties who know the arguments. Brevity differs from inadequacy, and a challenge complaining that the inspector dealt with a point in two sentences rather than two pages will usually fail.

There is a further hurdle even where an error is established. The court may decline to quash where it is satisfied the outcome would have been the same, so a challenge has to show the error was capable of affecting the decision.

The six week deadline and its strictness

Six weeks runs from the date the decision is taken, meaning the date on the decision letter rather than the date you received it. Diary it the day the letter arrives.

That period has to cover reading the decision, obtaining advice, drafting grounds, preparing the claim form and supporting documents, and issuing. Six weeks is enough only if the work starts immediately. In practice, the useful sequence is a first read within 48 hours to identify any candidate ground, counsel's opinion inside the first fortnight, and a decision to proceed with at least two weeks of drafting time in hand.

For enforcement appeal decisions the challenge route is section 289 rather than section 288, and for a decision of a local planning authority rather than an inspector the route is judicial review under Part 54 of the Civil Procedure Rules. Different routes, different time limits, and the wrong one is fatal. Check which applies before anything else.

Permission and the test applied

A section 288 application requires the permission of the court before it can proceed. The test at that stage is whether the claim is arguable, which filters out grounds that amount to disagreement with planning judgement dressed in legal language. Permission is usually determined on the papers, with an option to renew orally where refused.

The practical consequence is that grounds have to be pleaded precisely. Each ground should identify the error, the paragraph of the decision letter where it appears, the legal principle engaged and why the error was material to the outcome. A rolled-up ground asserting that the inspector erred in the overall balance is the kind that gets refused.

Remedies if the challenge succeeds

The remedy is narrow. The court quashes the decision and remits the appeal to the Secretary of State for redetermination. It does not grant planning permission, and it does not direct a particular outcome.

Redetermination may be by a different inspector, on the same or updated evidence, and the appeal is decided again against national and local policy as it then stands. That last point matters. Where policy has moved on since the original decision, a successful challenge can lead to a redetermination on a less favourable policy framework, and it is worth modelling that outcome before issuing.

Costs exposure

The general rule is that the unsuccessful party pays the successful party's costs, and costs in the Planning Court are substantial. The respondent is normally the Secretary of State, and the local planning authority or another party may participate as an interested party with its own costs.

Where a claim is an environmental claim within the Aarhus Convention rules, the Civil Procedure Rules cap the costs recoverable from the claimant and the claimant's recovery in turn. Whether a particular planning challenge qualifies is a point to take advice on, and the capped figures are set in the rules and change, so check the current version.

Budget for the permission stage separately from the substantive hearing, and ask for an estimate of both before issuing.

Practical alternatives to litigation

For most refused appeals, litigation is the wrong tool. The alternatives:

1. A revised application addressing the reason the appeal failed, which is often quicker and cheaper than a challenge and can use the fee-free further application where the criteria are met.
2. A fresh appeal on the revised scheme, with the inspector's reasoning on the earlier scheme as a guide to what needs to change.
3. Where the failure was evidential, commissioning the evidence the inspector said was missing and reapplying.
4. Asking the Planning Inspectorate to correct a slip in the decision letter where the error is clerical rather than legal.

Option one is the right answer far more often than clients want to hear. A decision letter that explains exactly why a scheme failed is, awkwardly, a useful brief for the next attempt. Choosing the right procedure first time reduces the risk of ending up here at all, which is why written representations, hearing or inquiry deserves real thought, and why the written representations timetable should be read before the appeal is lodged. Where the refusal concerned conditions rather than the principle of development, the route is narrower again, as with appealing a refused discharge of conditions.

A well-evidenced Planning Statement at application stage is the cheapest insurance against all of this. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. This is general guidance about the planning system, not legal advice; a High Court challenge needs advice from a solicitor and counsel specialising in planning law, and time limits are strict.