Employment Law in Practice: How Tribunals Assess Credibility and Conduct

Article summary:

• Employment Tribunals weigh the credibility of witnesses, the quality of documentation, and the conduct of both parties throughout the employment relationship and the proceedings themselves
• Tribunals apply a range of tests that are not about whether an employer was right, but whether they acted within the ‘band of reasonable responses’
• The consistency of an employer’s treatment across different employees, and across different disciplinary matters, is used by tribunals to assess whether a dismissal was genuinely motivated by the stated reason
• An employee’s conduct during the employment relationship, including how they raised concerns, whether they followed procedures, and how they behaved after dismissal, can reduce compensation even where the dismissal itself was unfair
• Contemporaneous documentation, created at the time events occurred rather than reconstructed for the purposes of proceedings, carries substantially more evidential weight than witness evidence about events recalled months or years later.

Employment Tribunals do more than apply the law. They assess whether an employer acted reasonably, whether their account is consistent with the documents, and whether the witnesses sitting in front of them are telling the truth. An employment law claim that looks straightforward on paper can unravel under cross-examination. A dismissal that appeared defensible can fall apart once the tribunal examines how the decision was actually reached. Understanding how those judgments are made, and what influences them, is just as important as understanding your legal rights. The law tells us what the test is. How a tribunal applies it in practice is a different question entirely, and one that determines far more outcomes than most people realise before they find themselves in proceedings.

What is the ‘band of reasonable responses’ test?

In unfair dismissal cases, a tribunal does not ask whether the employer made the right decision; it asks whether the decision was one that a reasonable employer could have made. This is what employment Solicitors call the ‘band of reasonable responses’. Imagine ten different reasonable employers all faced with the same situation: an employee caught stealing a small amount from the till. Some might dismiss the employee immediately. Others might issue a final written warning, particularly if the employee has a long and clean record. Both responses might fall within the band, or one might not. The tribunal decides on a case-by-case basis, drawing on its experience of how reasonable employers operate. As such, there is no definitive list of what falls inside or outside it, which is one of the reasons employment claims are genuinely difficult to predict with certainty.

The band applies equally to the process undertaken by the employer, not just the outcome. An investigation that was rushed or one-sided, a disciplinary hearing chaired by someone who had already made up their mind, or a sanction far more severe than the employer has previously imposed for comparable behaviour, can all fall outside the band even where the reason for dismissal was legitimate.

Consistency of treatment

Consistency of treatment is another test utilised by employment tribunals when assessing whether a stated reason for dismissal was the real one. Where an employer has dismissed one employee for conduct that other employees have committed without sanction, or where the disciplinary record reveals that the same behaviour attracts different consequences depending on who is involved, the tribunal will scrutinise the explanation carefully.

This scrutiny is particularly close in cases where the employee has recently raised a grievance, made a protected disclosure, or falls within a protected characteristic. An employer who dismisses an employee for an infraction that has previously been overlooked, in the weeks following a formal complaint about a manager, faces a significant evidential burden in demonstrating that the timing is coincidental rather than causal. Tribunals are not naive about the relationship between raising concerns and subsequent disciplinary action, and the closer the temporal connection, the harder that burden becomes to discharge.

Employers who maintain disciplinary records carefully, document the reasons for decisions at the time they are made, and review their own precedents before imposing sanctions are significantly better placed to demonstrate consistency than those who rely on management recollection of how previous situations were handled.

How employment tribunals read witnesses

Employment Tribunal hearings are conducted before an Employment Judge sitting alone in most unfair dismissal cases, or with two lay members in discrimination and certain other claims. The judge and members hear oral evidence from witnesses on both sides, ask questions directly, and form their own assessment of credibility. That assessment is not reducible to a checklist, but certain patterns recur across tribunal decisions consistently enough to be instructive. The judge will be looking for concessions, consistency, and demeanour.

Concession – A claimant who concedes that their performance had been a cause for concern, while maintaining that the dismissal was nonetheless disproportionate or discriminatory, is more persuasive than one who denies any legitimate criticism ever existed. A manager who accepts that the investigation could have been more thorough, while maintaining that the decision to dismiss was genuinely motivated by conduct concerns, tends to be better received than one who insists every aspect of the process was flawless.

Consistency – Consistency between witness statements and contemporaneous documents is really important. Tribunals read the documentary bundle before hearing oral evidence, and they notice when an account given in the witness box diverges from what was recorded at the time. Where a dismissal letter gives one reason and a manager’s witness statement gives a subtly different emphasis, the tribunal will want to understand why. Where a grievance investigation report summarises an employee’s complaint differently from the contemporaneous written complaint itself, that discrepancy requires explanation.

Demeanour – Demeanour under cross-examination also carries weight, though tribunals are trained to approach this with caution. A witness who becomes defensive, who provides different answers to the same question depending on how it is framed, or who volunteers information that was not asked for in ways that appear rehearsed, creates a less favourable impression than one who answers directly and acknowledges uncertainty honestly. Preparation for cross-examination is important, but over-preparation that produces scripted answers rather than genuine responses tends to be apparent to experienced judges.

Employee’s conduct during employment

Employment tribunals can reduce a compensatory award if they believe an employee’s own conduct contributed to their dismissal, or where their behaviour before, during, or after the dismissal was such that it would be just and equitable to reduce the compensation payable. These reductions can be substantial, with contribution findings of 25, 50, or even 100% not uncommon in cases where the employee’s conduct was a genuine factor in what occurred.

Contributory fault operates independently of whether the dismissal itself was fair or unfair. A tribunal can find that an employer followed a flawed process that rendered the dismissal procedurally unfair, while also finding that the employee contributed significantly to the situation that led to it. The compensation awarded in such a case will reflect both findings. An employee who succeeds in demonstrating unfair dismissal but is found to have contributed 50% may receive half the compensatory award that would otherwise have been appropriate.

An employee’s behaviour after dismissal can also affect their compensation. The duty to mitigate requires a dismissed employee to take reasonable steps to find alternative employment. A tribunal will assess whether the claimant has mitigated their losses effectively, and where it finds that they have not taken reasonable steps, whether by failing to apply for available positions, by unreasonably turning down suitable offers, or by deferring their job search, it will reduce the award to reflect the income that should have been earned. Claims supported by evidence of active, documented job searching tend to fare considerably better on this issue than those where the employment history since dismissal is unclear.

The Polkey reduction

Where a tribunal finds that a dismissal was procedurally unfair, it must consider whether a fair procedure would have made any difference to the outcome. If the tribunal concludes that the employee would have been dismissed in any event, even had a fair process been followed, it can reduce or extinguish the compensatory award on that basis – this is the Polkey reduction. Employers who can demonstrate that the reason for dismissal was overwhelming, and that a proper process would inevitably have produced the same result, significantly limit their financial exposure even where procedural failures are established.