Unfair dismissal win reduced by 80% Polkey cut and mitigation failure
A former employee won an unfair dismissal claim against Network Rail Infrastructure Limited, but saw compensation slashed by 80% because they would have been dismissed anyway, plus a further deduction for failing to look for work.
1 min read · Last updated 18 May 2026
Case details
- #polkey-deduction
- #mitigation-failure
- #remedy-hearing
Key facts
- The claimant was dismissed by the respondent.
- The dismissal was procedurally unfair.
- The claimant would have been dismissed by 11 April 2022 had a fair procedure been followed.
- The claimant failed to take reasonable steps to mitigate his loss.
- The respondent paid the claimant £17,575.66 on termination.
Timeline
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Dismissal
The claimant was dismissed by Network Rail Infrastructure Limited.
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Hypothetical fair dismissal date
The tribunal found that the claimant would have been dismissed by this date had a fair procedure been followed.
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Liability hearing day 1
The tribunal heard evidence and argument on liability.
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Liability hearing day 2
The tribunal concluded the liability hearing.
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Judgment on liability
The tribunal issued a reserved judgment finding unfair dismissal and ordering an 80% Polkey reduction.
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Remedy hearing
The tribunal calculated the award, applying the Polkey deduction and a deduction for failure to mitigate.
The legal issue
The tribunal had to decide whether the employee was unfairly dismissed and, if so, what compensation was appropriate, including whether to reduce the award because the employee would have been dismissed anyway (Polkey reduction) and for failing to take reasonable steps to find new work.
The outcome
The tribunal ruled that the former employee was unfairly dismissed by Network Rail Infrastructure Limited due to procedural failings. However, it found that a fair process would have led to dismissal by 11 April 2022, so an 80% Polkey reduction was applied to losses after that date. The employee also failed to take reasonable steps to mitigate their loss, leading to a further deduction.
Compensation breakdown:
- Basic award: £11,152
- Compensatory award: £11,619.39 (after deductions)
- Total award: £22,771.39
- Deductions: £17,575.66 termination payment, £10,727.75 for failure to mitigate, and 80% Polkey reduction applied to post-11 April 2022 losses.
Lessons & takeaways
- Even if a dismissal is procedurally unfair, compensation can be heavily reduced if the employer can show the employee would have been dismissed anyway.
- Claimants must actively seek work to mitigate their loss; failing to do so can lead to significant deductions from the compensatory award.
- The Polkey reduction applies only to losses after the date the employee would have been fairly dismissed, not to losses before that date.
- Representing yourself is possible but complex; understanding Polkey and mitigation principles is crucial for maximising compensation.
This case shows how even a successful unfair dismissal claim can result in a much lower payout than expected. The former employee, who represented themselves, proved that Network Rail Infrastructure Limited's dismissal procedure was flawed. However, the tribunal found that the employee would have been dismissed by 11 April 2022 even if a fair process had been followed, so an 80% Polkey reduction was applied to losses after that date.
The impact of failing to mitigate
The employee also lost a significant chunk of their compensatory award because they did not take reasonable steps to find a new job. The tribunal deducted £10,727.75 for this failure, highlighting the importance of actively seeking work after dismissal. Claimants should keep records of job applications and any other efforts to find employment.
What Network Rail could have done differently
Network Rail could have avoided the unfair dismissal finding by following a fair procedure. The tribunal did not specify the exact procedural flaw, but the case serves as a reminder that employers must give employees a fair opportunity to respond to concerns before deciding to dismiss. A fair process might have led to the same outcome but would have prevented the compensation award.
Why this matters for similar claims
This case illustrates two key principles in unfair dismissal law: Polkey reductions and mitigation of loss. Claimants should be aware that even if they win, their compensation may be substantially reduced if the employer can show a fair process would have led to dismissal anyway, or if the claimant does not make reasonable efforts to find new work. It also shows that representing yourself is possible, but understanding these legal principles is essential to avoid unexpected deductions.
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