This article applies to England and Wales.
Evidence in unfair dismissal judgments
In brief: In substantial unfair dismissal judgments from England and Wales, 2023–25, witness statements are mentioned in 67%, the contract of employment in 52%, written warnings and WhatsApp in 17% each, and dismissal letters in 16%. Since 2017–19 WhatsApp has risen from 3% and written warnings have fallen from 22%; the dismissal letter and investigation report have not moved.
Last updated: September 2026
By Yerty | Analysis of published Employment Tribunal decisions, 2017 to 2025. Part of the evidence by claim type series.
Unfair dismissal is the tribunal's staple claim, and its evidence profile is the population's profile: employer paperwork, witness statements, and a growing share of messages. Two things have changed in nine years. Judgments mention WhatsApp five times as often, and they mention written warnings a quarter less often.
This piece takes the unfair dismissal column of Yerty's evidence by claim type analysis and reads it on its own. Unfair dismissal is the largest claim type in the population (1,464 judgments in 2017–19, 1,085 in 2023–25), so its figures sit close to the all-cases column throughout; what is distinctive is the weight of disciplinary paperwork.
Summary
- The disciplinary paperwork is here. Investigation reports (14%), disciplinary policies (15%), dismissal letters (16%) and written warnings (17%) are all more common in unfair dismissal judgments than in the population as a whole (10–13%). This is where they live.
- Written warnings are described less. 22% of unfair dismissal judgments mentioned a written warning in 2017–19; 17% do now. Final written warnings fell from 16% to 13%. The dismissal letter (16% in both periods) and investigation report (14% in both) did not move.
- WhatsApp went from 3% to 17%. Screenshots from 1% to 3%; text messages, voicemail and photographs did not move.
- Medical evidence is a side issue. Occupational health 17%, fit notes 10%, impact statements 3%. These belong to disability claims, which often run alongside.
Evidence in unfair dismissal judgments
Share of judgments that mention each type of evidence at least once. The final column is every judgment in the population, for comparison. 1,464 judgments in 2017–19 and 1,085 in 2023–25.
Evidence mentioned in unfair dismissal judgments · share of judgments, ■ 2017–19 (n 1,464) → ■ 2023–25 (n 1,085) · ○ all cases 2023–25
Sorted by change. Rows under 3% in both periods are omitted; the full figures are in the table below. A mention is not reliance.
| Evidence | Unfair dismissal 2017–19 | Unfair dismissal 2023–25 | All cases 2023–25 |
|---|---|---|---|
| Witness evidence | |||
| Witness statement | 59% | 67% | 67% |
| Employer documents | |||
| Contract of employment | 51% | 52% | 50% |
| Written warning | 22% | 17% | 13% |
| Final written warning | 16% | 13% | 10% |
| Dismissal letter | 16% | 16% | 11% |
| Job description | 13% | 12% | 11% |
| Disciplinary policy | 16% | 15% | 11% |
| Investigation report | 14% | 14% | 10% |
| Resignation letter | 11% | 9% | 7% |
| Appeal letter | 8% | 7% | 6% |
| Employee handbook | 5% | 5% | 4% |
| Grievance letter | 5% | 4% | 4% |
| Personnel file | 3% | 2% | 2% |
| Pay and time paperwork | |||
| Payslips | 6% | 11% | 11% |
| Rota | 8% | 11% | 10% |
| P45 | 6% | 6% | 5% |
| Timesheets | 3% | 4% | 5% |
| Bank statements | 2% | 3% | 3% |
| Medical evidence | |||
| Occupational health | 18% | 17% | 17% |
| Fit note | 7% | 10% | 9% |
| Medical records | 3% | 4% | 4% |
| Impact statement | 2% | 3% | 4% |
| Medical report | 3% | 2% | 2% |
| Notes made at the time | |||
| Diary | 7% | 6% | 5% |
| Minutes of the meeting | 6% | 5% | 4% |
| Contemporaneous notes | 2% | 3% | 2% |
| Incident report | 3% | 2% | 2% |
| File note | 1% | 1% | 1% |
| Messages and images | |||
| 3% | 17% | 16% | |
| Text messages | 6% | 7% | 7% |
| Social media | 4% | 6% | 5% |
| Photographs | 8% | 6% | 5% |
| Screenshots | 1% | 3% | 3% |
| Microsoft Teams | 0% | 2% | 2% |
| Voicemail | 2% | 2% | 2% |
| Phone records | 1% | 1% | 1% |
n: Unfair dismissal 1,464 / 1,085; all cases 2,029 / 1,738. A judgment is counted under every claim type among its claims.
The disciplinary file
An unfair dismissal claim under section 98 of the Employment Rights Act 1996 turns on the employer's reason for dismissal and whether it acted reasonably in treating that reason as sufficient. The evidence of both is the employer's own process documents, and the table shows them concentrated here. An investigation report appears in 14% of unfair dismissal judgments against 6% of wages judgments and 3% of redundancy judgments; a disciplinary policy in 15% against 1% in redundancy.
Within that file, the movement is in warnings. Written warnings fell from 22% to 17% of judgments and final written warnings from 16% to 13%, while the dismissal letter, the investigation report and the disciplinary policy are unchanged. The hub analysis shows the same fall in every claim type, so it is not that fewer conduct dismissals reach tribunal. Judgments describe the ladder of prior warnings less often than they did, whether because fewer cases turn on it or because the disciplinary history is summarised more briefly.
Written warnings: share of judgments by claim type. The fall is in every line.
Each line is one claim type. Claim types overlap. The dashed line is the all-cases value in 2023–25.
Messages
WhatsApp is mentioned in 17% of unfair dismissal judgments, up from 3%. That rise is the same size as in the population (3% to 16%). Screenshots rose from 1% to 3%. Text messages (6% to 7%), social media (4% to 6%), voicemail (2%) and photographs (8% to 6%) are where they were. The messaging evidence that reached unfair dismissal judgments in 2023–25 is, in practice, WhatsApp.
What did not change
The contract of employment sits at 51–52% in both periods. Job descriptions (13% to 12%), resignation letters (11% to 9%), appeal letters (8% to 7%) and grievance letters (5% to 4%) moved by a point or two. Payslips rose from 6% to 11%, in line with the population, which reflects the wages claims that commonly travel with an unfair dismissal claim rather than anything about the dismissal itself.
Witness statements rose from 59% to 67%, the same as every other claim type; the hub analysis treats this as a change in how judgments are written as much as in what was before the tribunal.
Method and limits
Population and matching are those of the hub analysis: single-claimant merits decisions with written reasons, England and Wales, one judgment per case, 20,000 to 60,000 characters. Each figure is the share of judgments containing the exact phrase at least once. A judgment is counted under a claim type if that claim type is among its claims, so a judgment can appear in several claim-type columns and the columns do not sum to the population. A mention is not reliance: a judgment that rejected a document or noted its absence counts the same as one that accepted it. No category totals are given.
Frequently asked questions
What evidence appears most often in unfair dismissal judgments?
In substantial judgments from 2023–25: witness statements (67%), the contract of employment (52%), written warnings (17%), WhatsApp (17%), dismissal letters (16%), disciplinary policies (15%) and investigation reports (14%). Figures are England and Wales, single-claimant, one judgment per case, and count judgments that mention the evidence at least once.
Are written warnings mentioned less than they used to be?
Yes. Written warnings appear in 17% of unfair dismissal judgments in 2023–25 against 22% in 2017–19, and final written warnings in 13% against 16%. The same fall appears in every claim type, so it is not explained by a change in the kinds of case reaching tribunal.
How often is WhatsApp mentioned in unfair dismissal cases?
In 17% of substantial unfair dismissal judgments from 2023–25, up from 3% in 2017–19. Screenshots rose from 1% to 3% over the same period. Text messages, voicemail, social media and photographs did not move, so the growth in messaging evidence is almost entirely WhatsApp.
Is medical evidence common in unfair dismissal claims?
Not on its own. Occupational health is mentioned in 17% of unfair dismissal judgments, fit notes in 10% and impact statements in 3%, all close to the population average. Where medical evidence is prominent it is usually because a disability discrimination claim runs alongside the unfair dismissal claim.
Does a document being mentioned mean the tribunal relied on it?
No. The counts include judgments that rejected a document, gave it little weight or noted that it was missing. A judgment that says there was no investigation report counts the same as one that quotes from it. The figures describe what judgments discuss, not what decided the case.
Which unfair dismissal cases are included?
Single-claimant merits decisions with written reasons from England and Wales, one judgment per case, between 20,000 and 60,000 characters, where unfair dismissal is among the claims: 1,464 judgments in 2017–19 and 1,085 in 2023–25. A judgment with several claim types appears in each of them.
Analyse the data
See how often the disciplinary file, warnings and messages appear in unfair dismissal judgments like yours, by year and industry.
Intelligence Hub →Manage your evidence
An unfair dismissal claim is decided on the employer's process documents. Keep the letters, minutes and dates in order.
Case Hub →Sources
Analysis of published Employment Tribunal decisions, 2017 to 2025, drawn from the public register on GOV.UK under the Open Government Licence v3.0. Population as stated in the hub analysis; 1,464 judgments with an unfair dismissal claim in 2017–19 and 1,085 in 2023–25.
Related reading: what evidence do I need for an unfair dismissal claim, what evidence tribunal judgments describe, 2017 to 2025, and tribunal evidence is moving from paper to screen.
Other pieces in this series: disability discrimination, wages and working time, race, sex and age discrimination, whistleblowing, redundancy.