When an inspector decides on an issue nobody raised

An inspector who raises a new issue is not doing anything improper. The appeal is a fresh determination of the application, not an arbitration between two sets of submissions, so the decision maker is entitled to identify what matters and is not confined to the council's reasons for refusal or to the grounds of appeal. What the inspector cannot do is decide the appeal on a point neither party had a fair chance to address.

That is the line, and it is narrower than most appellants assume. Disappointment at an unexpected reason is not unfairness. Deciding the appeal on an issue that surfaced for the first time in the decision letter usually is.

How main issues are identified

For an inquiry, the main issues emerge through the case management conference, the statement of common ground, the statements of case and the inspector's pre-inquiry note. For a hearing, the inspector sets out the agenda. For written representations, the issues come from the reasons for refusal, the grounds of appeal and the representations received.

Three sources of a new issue, in order of frequency:

• A policy in the development plan that neither party cited, which the inspector is obliged to apply because section 38(6) of the Planning and Compulsory Purchase Act 2004 requires the determination to be made in accordance with the plan unless material considerations indicate otherwise.
• A point raised by an interested party, which the inspector takes up and the main parties had treated as peripheral.
• A change in the policy background between the inquiry and the decision, such as a new framework, a newly adopted plan or a court judgment.

The first is the one practitioners underestimate. An inspector who notices that a site is within a Local Green Space allocation, or that a development plan policy on employment land applies to a use neither party had characterised that way, will deal with it whether or not it was pleaded.

Points the inspector raises during the process

Most new issues surface while the process is still running, and that is the good outcome. The inspector may put the point in a written question, raise it at the opening of an inquiry, ask about it during a round table session, or send a note after the site visit.

Treat each of those as an invitation rather than an interruption. The response that works is a short focused note dealing with the point, filed within the time given, with any supporting policy extract attached. Where you need evidence you do not have, say so and ask for time rather than offering an assertion.

The last two rows are where the law bites.

The opportunity to respond

The inquiry procedure rules allow an inspector who needs further information after the close of an inquiry to invite written representations or to reopen the inquiry. The same facility exists in substance for hearings and written representations. The decision to use it is the inspector's, and a party who thinks a point needs addressing should ask rather than assume.

What matters for later is the record. Write to the Planning Inspectorate, copy the council and any other main party, identify the point, say why it was not covered and what you would say about it. That letter is the document a court will look at if you later argue you were denied a fair chance.

Keep it proportionate. A request to reopen an inquiry over a point of emphasis will be refused, and the correspondence then reads as an attempt to have the last word. Reserve it for points capable of changing the outcome. Our note on reading a refusal notice and turning it into a plan covers how to spot early which issues are decisive.

Natural justice and where it is breached

The Court of Appeal addressed this in Hopkins Developments Ltd v Secretary of State for Communities and Local Government, which remains the starting point. The principles are practical rather than abstract. Each party must know what case it has to meet. If the inspector intends to decide on a basis the parties have not addressed, they must be given the opportunity to deal with it. But a party cannot complain simply because the inspector reached a different view of the evidence, or weighed a disclosed issue differently, or relied on their own professional judgement in a field where judgement is expected.

So the test has two limbs that have to be satisfied together: the point was not fairly open to the party on what it knew, and the party suffered real prejudice because it had evidence or argument it was unable to deploy.

An illustrative example. An appeal on a 60 dwelling scheme is fought on landscape character and housing land supply. The decision letter dismisses the appeal principally because the access would be unsafe in winter conditions, a matter the highway authority had not objected to and which was never raised. The appellant had a stage one road safety audit it never produced because nobody suggested safety was in issue. That is prejudice as well as surprise. By contrast, a decision that dismisses the same appeal because the inspector found landscape harm moderate rather than slight is simply a different judgement on a disclosed issue. This example is illustrative.

Conditions imposed that nobody proposed

Inspectors frequently impose conditions that appeared in neither party's schedule, and they are entitled to. The usual position is that conditions are discussed at the inquiry or in a round table, with a signed schedule agreed, and the inspector may then add, amend or renumber.

The problem arises where a condition changes the scheme rather than controlling it. A condition that reduces the number of units, removes an access, requires a different drainage strategy or imposes a restriction that makes the development undeliverable goes beyond refinement. Practice is for the inspector to raise such a condition with the parties before imposing it, and a failure to do so can be unfair on the same principles.

Two defensive habits. Submit a conditions schedule with a short justification against the six policy tests for each condition, so the inspector has a drafted alternative to work from. And where a condition is discussed orally, ask for the agreed wording to be recorded in writing before the inquiry closes.

If a condition imposed on a grant is unacceptable, remember there are two routes: a challenge to the whole decision, and an application under section 73 to vary the condition. The second is usually faster and carries less risk.

Reading the decision for unexpected reasoning

Read the decision letter twice in the first week, and the second time with a specific question: on what basis was this actually decided?

Work through it mechanically. List the main issues the inspector identified in the decision. Compare that list with the main issues as understood during the process. For each conclusion, identify the evidence relied on and check it was in the evidence base. Note any policy cited that no party cited. Note any factual finding that neither party put forward, particularly findings made from the site visit.

Site visit findings deserve attention. An inspector is entitled to use their own eyes, and a conclusion about intervisibility, noise or character drawn from the visit is ordinarily sound. A conclusion that depends on something not visible from where the visit took place, or on a measurement nobody took, is a different matter.

The cases where interested parties have the clearest picture are those where they attended throughout, which is one reason to read our note on what objectors can do once a planning appeal starts alongside this.

Challenging on procedural grounds

An inspector's decision is challenged by application to the Planning Court under section 288 of the Town and Country Planning Act 1990, within six weeks of the date the decision is issued. The court tests legality, and procedural unfairness is an established ground.

To succeed you need to show three things. That the decision turned on the point. That you did not have a fair opportunity to address it. And that you had something to say which might realistically have made a difference, which usually means identifying the evidence or argument you would have advanced. A challenge that complains of surprise without demonstrating prejudice fails at permission stage.

The six weeks is tight, so the sequence is: read the decision in week one, take counsel's view in week two, and decide by week four. And keep the correspondence from the appeal itself, because a letter asking the inspector to deal with the point, sent at the time and copied to the other parties, is worth more than any later reconstruction of what you would have said.

A well structured appeal statement reduces the chance of being surprised in the first place, because it frames the issues rather than responding to them. PlanScope can draft the Planning Statement and appeal narrative to the policy structure, with citations and flags where evidence is still needed. Where highway safety is likely to feature, our note on highway safety refusals and the evidence that answers them sets out what to have ready.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it.

PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.