Guide · Complaints & Disputes

Building evidence

Build an evidence set that is easy to verify: documents, screenshots, calls, bills, contracts, metadata and notes made at the time.

Evidence is what lets a disputed fact be tested; collect it by issue, not just by volume.

Good evidence answers a question. A bill proves a charge, a call recording can prove what was said, a screenshot can preserve a webpage, and an internal note obtained through a SAR can show how an organisation recorded an event. The strongest case is not necessarily the one with the most documents - it is the one where the important documents are easy to find and understand.

Keep original files where possible and avoid altering screenshots or PDFs. Create working copies for highlighting, but preserve the source material.

Key points

  • Prefer records made at the time created at the time over later recollections where available.
  • Record provenance, where the document came from and when you obtained it.
  • Use descriptive filenames and an evidence index.
  • Distinguish evidence of a fact from evidence of someone’s opinion about that fact.

Common evidence types

Contracts/order recordsWhat was agreed and when
Bills/statementsCharges, payments and balances
Emails/messagesWhat each party said at a particular time
Call recordings/transcriptsSales promises, complaints and admissions
ScreenshotsOnline journey, status or public wording at a point in time
Internal SAR recordsHow the organisation recorded decisions/events
Credit reportsWhat was reported externally and on what date
Expert reportsTechnical cause, defect or value where specialist knowledge is needed

Evidence needs context

A screenshot without a date or account context may be difficult to interpret. A single internal code may be meaningless without the surrounding record. Add a short index description explaining why each item matters.

Preserve conflicting versions

If a company later changes a document, explanation or chronology, keep both versions. Do not overwrite the earlier one. Version differences can become evidence in their own right.

In practice

  • Create folders by issue or date and name files consistently.
  • Keep the raw download from a SAR/portal before rearranging it.
  • For phone calls, make a note at the time of the call, including the time, participants and key points even if a recording may later be available.

Evidence worth keeping

Issue list
Chronology
Evidence index
Key correspondence
Final response/deadlock letter
Any decision and scheme rules/terms of reference

Create an evidence index before escalation.

Useful columns.

Ref | date | document | source | proposition proved | relevant issue.

A reviewer should be able to move from your issue list to the supporting document in seconds.

Preserve metadata and context.

  • Keep full emails with date/sender/recipient
  • Save web pages/screenshots with date and URL where possible
  • Keep complete bills, not cropped line items only
  • Retain tracking numbers and return confirmations
  • Record where SAR/FOI material came from
  • Do not alter original files; annotate a copy if needed

Context protects against the other side saying a quote was selective or detached from the document.

Prefer contemporaneous and primary records where possible.

Original contracts, recordings, bills, system records, receipts and messages created at the time often carry more evidential weight than later recollection. Later summaries can still help, but identify them as summaries rather than treating them as the original event.

Collect evidence by proposition.

Ask what you need to prove: price, date, promise, payment, fault, notice, loss, complaint or data entry. Then collect the strongest source for that proposition. This avoids a common mistake: hundreds of pages of records with no explanation of what any page proves.