Proof of evidence: a working structure for a witness

A proof of evidence is written for the inspector, read by the advocate and tested by the other side's barrister. Those three audiences want different things from the same document, and the structure below keeps all of them served. It follows the sequence the Planning Inspectorate expects for an inquiry: qualifications and declaration, scope, the case in chief, the response to the opposing case, then conditions and obligations, with a summary where the proof runs beyond 1,500 words.

Get the structure right and cross-examination becomes an argument about planning judgement. Get it wrong and it becomes an argument about your document.

Qualifications and declaration

Open with who you are, what you are qualified to say and on whose instructions you are saying it. Keep it to a page. Name your professional body and grade of membership, the years of relevant experience, and the specific experience that matches the issue in dispute, rather than a general career summary.

Then the declaration. State that the evidence is your own, that it is true, and that the opinions expressed are your professional opinions regardless of who instructed you. Expert witnesses owe their primary duty to the tribunal, and both the RTPI and RICS expect members acting as experts to say so on the face of the proof. Where you have had a prior involvement with the site, disclose it here. A previously undisclosed role that surfaces in cross-examination damages everything that follows it.

If part of your evidence relies on someone else's work, such as survey data or a traffic model, say which parts, who produced them and that you have satisfied yourself they are sound.

Scope of evidence and instructions

Set out the issue or issues your proof addresses, tied to the reasons for refusal or the main issues identified at the case management conference. Say plainly what you do not cover and who covers it. Overlapping proofs from the same team waste inquiry time and invite the question of which witness the inspector should believe.

This section should also record the documents you rely on, by reference to the core document list rather than reproducing them. If a Statement of Common Ground has been agreed, say what it settles, because everything it settles is time you do not spend at the inquiry.

The case in chief

This is the substance. Structure it by the issue, not by the chronology of the planning application.

1. Identify the development plan policies engaged and set out their proper interpretation.
2. Apply them to the facts of the site, using evidence rather than assertion.
3. Deal with the National Planning Policy Framework, stating the edition you are working from, and any national guidance that bears on the issue.
4. Identify the harm and the benefits in the planning balance, giving each the weight you say it deserves and explaining why.
5. Reach a conclusion that the inspector could adopt as a paragraph of the decision letter.

That last point is the working test. If your conclusion cannot be lifted, with the reasoning intact, into a decision letter, it is not finished.

Write in the first person and in plain sentences. Avoid the drafting habit that stacks up qualifications until no proposition remains. If you hold a view, state it and give the reasons. If you hold it with reservations, name the reservation once, in a sentence.

Responding to the other side

A proof is exchanged, not published in a vacuum, so anticipate the opposing case from the statements of case rather than waiting to write a rebuttal.

Deal with the strongest point against you directly. Every inspector notices when a proof addresses three weak objections in detail and passes over the difficult one in a clause. Acknowledging a point and explaining why it does not outweigh your case is stronger than pretending it does not exist, and it is far stronger than being led to the same acknowledgement under cross-examination.

Rebuttal proofs are for genuine new material. Where the inspector allows them, keep them short and confined to matters you could not reasonably have anticipated. A rebuttal that rehearses the main proof irritates.

Conditions and obligations

Whatever your case, include your position on conditions and on any section 106 obligation, usually as a schedule. Doing so is not a concession that permission should be granted, and inspectors expect both parties to engage with it.

Each suggested condition should have its purpose noted and should meet the six tests in national policy: necessary, relevant to planning, relevant to the development permitted, enforceable, precise and reasonable in all other respects. Where a pre-commencement condition is proposed, note whether the applicant has agreed to it in writing, because the statutory procedure requires that agreement to be sought.

For obligations, state which regulation 122 tests each head of terms satisfies. If your case is that an obligation fails those tests, say so here rather than leaving it to closing submissions.

Summary proof and word limits

Where the proof exceeds 1,500 words, the inquiry rules require a summary. Treat it as the document the inspector will read on the train, not as an abstract.

Write it last, keep it to the structure of the full proof, and make sure every conclusion in the summary appears in the same terms in the main text. Divergence between the two is a favourite opening for cross-examination. Number the paragraphs of both documents and cross-reference the summary back to the main proof so the inspector can find the reasoning quickly.

At the inquiry you are usually taken as having read your proof and asked to present the summary. Practise reading it aloud. Sentences that work on paper often do not survive being spoken.

Appendices that earn their place

Appendices should be evidence, not padding. Each one needs a reason to exist stated in the main text, and each should be paginated and indexed.

• Site photographs, dated and with viewpoint locations marked on a plan.
• Extracts of policies you rely on, where the core documents do not already include them.
• Appeal decisions you say are indicative, with the relevant paragraphs marked and a note of the material similarities and differences.
• Data underpinning any calculation, in a form that allows the other side to reproduce it.

Resist appending the entire local plan. And do not append documents you have not read closely, because an appendix is part of your evidence and can be cross-examined on.

An illustrative sequencing point: a landscape witness at a two-day inquiry appended 60 photographs without viewpoint plans. Half the second morning went on establishing where each was taken from, time that came out of the substantive evidence. The fix was a single annotated plan.

Before you sign it

Read the proof once for accuracy, once for tone and once against the reasons for refusal to be certain each is answered. Check every policy reference against the adopted document and every Framework reference against the edition in force, since the Framework has been re-issued more than once and paragraph numbering has changed.

The policy analysis that underpins a proof is usually the same analysis that should have appeared in the Planning Statement at application stage. Where it was done properly then, the proof is quicker to write, which is also the argument for a disciplined cover letter structure for a planning submission and for evidence checklists such as evidencing a vacant building credit claim being completed at the outset.

PlanScope drafts policy-structured planning documents that can form the evidence base behind an appeal, with missing site facts flagged rather than invented. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. Start from the postcode to see what your site needs.

This is general guidance on inquiry practice, not legal advice. Check the current procedural guidance and the inspector's case management directions before finalising any proof.