Statements of common ground and expert conferencing
A statement of common ground should settle facts, data and method, then record disagreement precisely. How topic statements and expert conferencing work at a planning inquiry.
A statement of common ground exists to take agreed matters off the inquiry timetable so the inspector spends hearing time on the things that are actually in dispute. On a planning appeal heading to inquiry, the statement of common ground inquiry document is usually the first joint paper the parties produce, and the discipline it imposes on both sides is worth more than the paper itself. Get it wrong and you spend two days of inquiry proving facts nobody disputes.
What a statement of common ground is for
The Planning Inspectorate's procedural guidance asks for a statement of common ground at a fixed point in the appeal timetable, before proofs of evidence are exchanged. Its purpose is narrow: to record the facts, the policy framework and the technical outputs that the appellant and the local planning authority accept, so that the inspector arrives knowing what is settled.
It is not a pleading and it is not advocacy. An inspector reading a statement that argues the appellant's case has learned something about the appellant, but nothing useful about the appeal.
The document also does work outside the inquiry room. Where a site visit is accompanied, an agreed site description saves an hour of argument about what is visible from where. Where conditions are in issue, an agreed schedule with the two disputed conditions marked as such focuses the discussion.
Matters that can be agreed and matters that cannot
The reliable division is between fact, method and judgement.
Facts agree easily: site area, the extent of the application site, distances to designated assets, the adopted development plan and its date, the housing land supply figures both sides are working from, correspondence dates, consultation responses received. Method often agrees too: the survey standard applied, the model used, the receptor locations, the baseline year.
Planning judgement does not agree, and should not be dressed up as if it did. Whether harm to a heritage asset is less than substantial is a judgement for the decision maker. Whether a conflict with a policy is outweighed by benefits is the appeal. If an expert finds themselves agreeing a conclusion of that kind in a joint document, they have stepped into the inspector's role.
There is a middle band that causes most of the trouble. Sentences like "the parties agree the effect is not material" look factual and are not. Better practice is to record the number both sides accept and leave the characterisation to the proofs.
Topic statements on technical subjects
On larger inquiries the single statement splits into topic based statements, each prepared by the relevant experts: highways, ecology, heritage, noise, flood risk, viability. The advantage is that a transport planner and a highway authority officer can agree trip generation rates, junction geometry and accident data in a document neither planning witness needs to touch.
A workable topic statement usually contains:
- the agreed baseline data and its source and date
- the methodology applied and any departures from the standard
- the model inputs both sides accept
- the outputs, stated as numbers
- a short list of the specific matters not agreed, each in one sentence
- any survey that has expired or needs updating before the inquiry
That last item earns its place. Ecology and noise data have a shelf life, and the point to raise it is in the statement, not in cross examination. Our note on checking whether a survey is still valid sets out the usual periods.
Who drafts, who signs and who is bound
Convention is that the appellant drafts first and the authority marks up, largely because the appellant holds the technical outputs. Nothing requires that order, and on appeals where the authority holds the local evidence it makes more sense the other way.
Signature matters. A topic statement should be signed by the two experts who prepared it, not by solicitors on their behalf, because the value of the document rests on professional acceptance of the content. An expert who signs a statement recording an agreed methodology has accepted that methodology, and will be asked about it.
The authority's signatory needs actual authority to bind the council on the points recorded. A case officer can agree the site area. Agreeing that a policy is out of date, or that a five year supply cannot be demonstrated, is a different order of concession and needs sign off further up. Appeals go badly when the council's advocate disowns a statement its own officer signed.
Where a witness is adopting technical work carried out by others, the position is the same as for any signed report. The person signing takes responsibility for it. What that means in practice is set out in our piece on what "competent person" means in planning legislation.
How agreement narrows an inquiry
The Rosewell review of planning appeal inquiries, published by government in 2019, pushed inquiries towards shorter timetables and more use of round table sessions in place of formal evidence. Expert conferencing, where the inspector chairs a discussion between two or three experts on one topic, only functions if the ground has been cleared first. Without an agreed data set the session becomes a slow argument about inputs.
Conferencing suits topics where the dispute is technical and narrow: a disagreement about a single junction capacity output, the appropriate condition survey period for a habitat, the receptor used for a noise calculation. It suits heritage judgement less well, because the disagreement there is about weight rather than method.
Prepare for a round table differently from cross examination. You need your numbers, your methodology and the two or three points of departure at your fingertips, and you need to be able to concede a minor point without treating it as a loss. Inspectors notice which experts can do that.
Recording disagreement properly
The professional obligation runs the other way too. An expert must not agree something to be helpful, to shorten the inquiry, or because the client's advocate would prefer it. If your view is that the ecological survey effort was inadequate, the statement records that, in a sentence, with the reason.
The formula that works is plain: what the parties disagree about, why, and what each says the consequence is. Three sentences per issue. Vague wording here is a trap, because an inspector reading "the parties disagree about ecology" has to spend inquiry time finding out what the disagreement is, and will ask the witness who wrote the sentence.
One honest difficulty. Experts under commercial pressure on repeat instructions do sometimes soften disagreement in joint documents, and the appeal process has no reliable mechanism to catch it. The protection is personal rather than procedural: the statement carries your signature, and you will be asked about it under oath.
Timetabling the exchange
Work backwards from the exchange date in the Inspectorate's timetable and allow three drafts. A single round of comments almost never converges, because the first authority mark up typically deletes conclusions rather than replacing them.
A sequence that tends to hold:
- Agree the topic split and who drafts each statement, within a fortnight of the start letter.
- Circulate skeleton statements with headings and agreed data tables, before any narrative.
- Exchange marked up drafts, with the disputed matters listed separately from the agreed text.
- Hold a short call between the two experts on each topic, not between the solicitors.
- Sign and submit by the timetabled date, listing any matter still open rather than leaving it out.
Leave the disagreement list until last and it will be written in a hurry, which is how imprecise wording reaches the inspector. Draft it first instead, as soon as the proofs are outlined, and treat the agreed sections as the easier half of the job. Drafts of the supporting statements that sit behind an appeal can be produced quickly, and PlanScope's professional directory is the route to a reviewer who will put their name to the technical work. Reports should be reviewed before submission, and PlanScope does not guarantee planning approval. For specialist technical reports, qualified professional input may be required. This is general guidance and not legal advice, so check the position with your local planning authority or a qualified professional before relying on it.
Browse the 66 PlanScope report types to see which evidence a scheme of this kind usually carries into an appeal.
Frequently asked questions
When is a statement of common ground required?
The Planning Inspectorate's procedural guidance sets the date in the appeal timetable, normally before proofs of evidence are exchanged. Check the start letter for the exact deadline, because timetables differ between written representations, hearings and inquiries. On inquiries the statement is expected early enough to shape the inspector's view of what needs evidence.
Who should sign a topic based statement of common ground?
The two experts who prepared it, one for each main party, rather than their solicitors. The document's value rests on professional acceptance of the data and the method, so the people who take responsibility for that should sign. Check that the authority's signatory has authority to bind the council on the points conceded.
Can an expert agree a planning conclusion in a statement of common ground?
No. Facts, baseline data and methodology are the proper subject of agreement. Whether harm is less than substantial, or whether benefits outweigh a policy conflict, is judgement for the decision maker. Recording numbers and leaving the characterisation to proofs of evidence keeps the expert inside their role.
What is expert conferencing at a planning inquiry?
A session chaired by the inspector in which experts on one topic discuss their disagreement directly instead of giving formal evidence and being cross examined. The Rosewell review encouraged round table sessions of this kind. They work when the data and method are already agreed and the dispute is narrow and technical.
What happens if the parties cannot agree the statement?
Submit it by the timetabled date with the disagreement recorded, rather than submitting nothing. List each open matter, the reason for the disagreement and what each party says the consequence is. An inspector can work with a statement that is honest about its gaps; a missing document costs inquiry time.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.