Unfair Dismissal: A Guide for UK Employers

Most unfair dismissal claims are not about whether the employee did something wrong. They’re about whether the employer followed the right process, applied the right test, and made a reasonable decision. Get the substance right but the process wrong, and you’ll pay for it. Get the process right but the substance wrong, and you’ll pay for it too. This guide covers both.

The Burchell Test: The Starting Point for Every Misconduct Dismissal

If you dismiss an employee for misconduct, employment tribunals apply the test established in British Home Stores Ltd v Burchell [1978] IRLR 379 EAT. The test has three elements: (i) the employer genuinely believed the employee was guilty of the misconduct; (ii) there were reasonable grounds for that belief; and (iii) the employer had carried out a reasonable investigation before forming that belief.

Each element is distinct. Genuine belief is subjective — tribunals will not substitute their own view of the evidence for the employer’s. But genuine belief alone is not enough. The employer must have had reasonable grounds for the belief — there must be evidence capable of supporting the conclusion, not just a hunch or a preference. And the investigation must have been reasonable — proportionate to the seriousness of the allegation, thorough enough to put the employer in a position where it could properly evaluate the evidence.

This matters enormously in practice. An employer who dismisses an employee for theft because a colleague said they saw it, without interviewing the employee, without checking CCTV, and without getting the colleague’s account in writing, may genuinely believe the employee is guilty — but the investigation was unreasonable. The Burchell test is not satisfied. The dismissal is unfair, even if, as it turns out, the employee did steal.

Conversely, an employer who investigates thoroughly, puts all the evidence to the employee, gives the employee a fair opportunity to respond, and still concludes — reasonably — that the employee is guilty, will satisfy the Burchell test even if the employee’s denial was credible. The standard is not proof beyond reasonable doubt. It is the standard of a reasonable employer who has carried out a reasonable investigation.

The Band of Reasonable Responses

Once the Burchell test is satisfied, the tribunal still asks whether dismissal was within the “band of reasonable responses” open to a reasonable employer. The leading case is Iceland Frozen Foods Co Ltd v Jones [1983] IRLR 439, where the EAT articulated the principle clearly: the tribunal must not substitute its own view for that of the employer. The question is not what the tribunal would have done. The question is whether dismissal was within the range of responses that a reasonable employer could choose.

This means that even if a tribunal would personally have given a final written warning, if dismissal was a response that a reasonable employer could reasonably have chosen, it will be fair. The band is wide. For serious misconduct — dishonesty, violence, gross insubordination — dismissal will almost always be within the band. For less serious matters, it depends on the circumstances: previous warnings, mitigating factors, consistency with how similar cases have been handled in the past.

The band test applies to the procedure as well as the outcome. In Sainsbury’s Supermarkets Ltd v Hitt [2003] IRLR 23, the Court of Appeal confirmed that the reasonableness of an investigation is also assessed by reference to the band of reasonable responses — not by whether the tribunal thinks the employer could have done more. This narrows the scope for procedural challenges: minor investigation gaps do not automatically make a dismissal unfair.

Gross Misconduct: What It Is and Isn’t

There is no fixed legal definition of gross misconduct. The label describes conduct that is so serious that it justifies immediate dismissal — summary dismissal without notice. Common examples: dishonesty, serious violence towards colleagues or customers, significant health and safety violations, serious insubordination, being under the influence of alcohol or drugs at work, deliberate unauthorised disclosure of confidential information.

But the label “gross misconduct” in a contract or disciplinary policy does not automatically mean that dismissal is fair. The Burchell test still applies. An employment tribunal will examine the actual facts, the investigation, and whether dismissal was within the band of reasonable responses. An employer who inserts a sweeping list of “gross misconduct” offences in their handbook and dismisses for any of them without a proper investigation will lose at tribunal.

Courts have found that conduct labelled as gross misconduct in policies did not justify dismissal in the specific circumstances: an employee who was drunk at a work Christmas party in circumstances where alcohol had been supplied freely by the employer; an employee who made an off-colour comment in a private WhatsApp group but had no prior warnings and a 12-year clean record; an employee found with a small amount of personal-use drugs off company premises but with a connection to the workplace. In each case, the question was whether dismissal was within the band of reasonable responses given all the circumstances — not whether the act could technically be categorised as gross misconduct.

The Investigation: Getting It Right

An inadequate investigation is the single most common reason employment tribunals find dismissals unfair. The investigation phase runs from the moment you become aware of the allegation to the moment the disciplinary hearing is convened. It determines whether you have a foundation for the hearing at all.

Appoint an investigating manager who is not the person who will make the dismissal decision. This is a basic procedural requirement: the decision-maker needs to come to the case with an open mind, and if they’ve been the one collecting evidence, that independence is compromised. For minor misconduct, a line manager can investigate; for serious allegations, consider using HR, a more senior manager, or in some cases an external investigator.

Suspension during investigation should only be used when necessary — where the employee’s continued presence would compromise the investigation (e.g. risk of interfering with evidence or witnesses), where there is a risk to colleagues, or where the allegation is so serious that continued working is untenable. In Whitbread plc v Hall [2001] IRLR 275, the Court of Appeal confirmed that automatic suspension on investigation — without any genuine consideration of whether it is warranted — is not a neutral act and can itself contribute to a finding of unfairness. Suspension should be reviewed regularly, paid, and lifted as soon as the reason for it ceases to apply.

Interview the accused. This seems obvious, but some employers present the employee with a list of allegations and ask them to respond in writing without a face-to-face meeting. A written response to a written allegation can work in straightforward cases, but for serious misconduct, a proper investigatory interview — with the employee having advance notice of the topics to be discussed and the right to be accompanied — is the appropriate approach. Get the responses in writing. If the employee claims witnesses who can corroborate their account, you should pursue those witnesses.

Preserve documents. If the allegation involves emails, system access logs, CCTV footage, or HR records, secure them immediately. Employment tribunal disclosure obligations will require you to produce relevant documents, and a failure to preserve them — particularly if the documentation would have been favourable to the employee — can damage your credibility significantly.

How long should an investigation take? Long enough to be thorough; short enough that it doesn’t look like harassment. A simple misconduct allegation might be investigated in a few days. A complex allegation involving multiple witnesses, technical evidence, or financial records might take several weeks. The ACAS Code says matters should be dealt with promptly — this is a real obligation. An investigation that takes six months without a clear reason will be scrutinised.

The Disciplinary Hearing

Once the investigation is complete, the employee must be given reasonable notice of the hearing. The ACAS Code recommends a minimum of 24–48 hours, though for serious allegations or complex disciplinary matters, more notice is appropriate. The employee is entitled to know the charges against them, to have copies of the documentary evidence the employer will rely on, and to have time to prepare their response.

Under s.10 of the Employment Relations Act 1999, the employee has the right to be accompanied at a disciplinary hearing by a trade union representative or a fellow worker. This right cannot be excluded or watered down. If the employee makes a reasonable request to be accompanied, you must accommodate it. Refusing, or holding the hearing without the companion present without good reason, is a breach of statutory rights and can result in an award of up to 2 weeks’ pay. More significantly, in a tribunal claim, it will be used as evidence that the process was unfair.

The decision-maker — the person who will decide whether to impose a sanction — should not have been the investigating manager. The hearing itself should give the employee a genuine opportunity to respond to each allegation, to challenge the evidence, and to put forward any mitigation. It is not an interrogation. It is a hearing. Take notes. If a relevant witness is not available to attend, consider whether to adjourn for them to be present rather than proceeding without them on contested facts.

After the hearing, the decision-maker considers the evidence and reaches a decision. The sanction must be proportionate — an employee dismissed for a first offence of minor misconduct, where a verbal warning would have been appropriate, has been treated disproportionately. Consider: the severity of the misconduct; the employee’s length of service and clean record; any mitigating factors raised at the hearing; consistency with how similar cases have been handled.

A word on after-acquired evidence — evidence that comes to light after the dismissal. The general rule from W Devis & Sons Ltd v Atkins [1977] AC 931 is that after-acquired evidence can be relevant to the fairness of a dismissal, but only in limited circumstances. If the employer discovers, after dismissal, evidence that would have justified dismissal on different grounds (e.g., the employee was also guilty of undisclosed theft), the after-acquired evidence can reduce compensation but cannot turn an otherwise unfair dismissal into a fair one. The fairness of the dismissal is assessed on what the employer knew at the time it decided to dismiss.

Automatically Unfair Dismissal

Certain categories of dismissal are automatically unfair — no qualifying period of employment is required, and the usual “band of reasonable responses” test does not apply. If the dismissal falls into one of these categories, the employer has no defence on the substantive reason for dismissal, though the compensation may still be affected by the employee’s contribution to the situation.

The categories are wide. Dismissal is automatically unfair if the principal reason is:

Pregnancy or maternity (s.99 ERA 1996): the employee is pregnant, has recently given birth, is on maternity leave, or is exercising other parental leave rights. Automatically unfair, uncapped compensation for the discrimination element.

Whistleblowing (s.103A ERA 1996, PIDA 1998): the employee has made a protected disclosure — a qualifying disclosure about wrongdoing which they reasonably believe to be in the public interest. Automatically unfair, and compensation is uncapped. This is the most financially dangerous category for employers — there is no ceiling on what a successful claimant can recover.

Trade union activities (s.152 TULRCA 1992): the employee is or proposes to become a trade union member, has taken part or proposes to take part in trade union activities, or is not a trade union member.

Working time rights (s.101A ERA 1996): exercising rights under the Working Time Regulations 1998 — refusing to work more than the 48-hour limit, taking rest breaks, or asserting annual leave entitlement.

Part-time worker status (Reg 7 Part-Time Workers Regulations 2000): the employee has asserted or exercised rights under the part-time workers regulations.

Fixed-term employee status (Reg 6 Fixed-Term Employees Regulations 2002): asserting rights under the fixed-term regulations.

National minimum wage rights (s.104A ERA 1996): the employee has taken action or is entitled to take action to enforce minimum wage rights.

Health and safety activities (s.100 ERA 1996): the employee is a health and safety representative, has raised health and safety concerns, or has refused to work in circumstances of serious and imminent danger.

Jury service (s.98B ERA 1996): the employee has been absent due to jury service.

Asserting a statutory right (s.104 ERA 1996): the employee has brought proceedings or asserted a statutory right under the Employment Rights Act.

None of these require two years’ continuous employment. An employee on day one can bring a claim for automatically unfair dismissal in any of these categories. The whistleblowing category deserves separate emphasis: the compensation cap does not apply, special award provisions can result in very large awards, and interim relief (requiring the employer to continue paying the employee pending the hearing) is available. If you are dismissing someone who has recently raised a complaint that could be characterised as a whistleblowing disclosure, take specific legal advice before proceeding.

The Polkey Deduction

In Polkey v AE Dayton Services Ltd [1988] AC 344, the House of Lords held that a procedurally unfair dismissal is still unfair — the employer cannot escape liability by arguing “it would have made no difference”. However, the tribunal can reduce the compensatory award — sometimes dramatically — if the employer can demonstrate that a fair procedure would have made no difference to the outcome.

This is the “Polkey deduction”. If, for example, an employer carries out a flawed investigation but the evidence against the employee was overwhelming and dismissal was inevitable, the tribunal may find the dismissal unfair on procedural grounds but reduce the compensatory award by, say, 70–80% to reflect the chance that the employee would have been dismissed anyway even if the procedure had been followed correctly. In an extreme case — where dismissal was truly inevitable — the deduction can be 100%, leaving the employee with only the basic award.

For employers, the Polkey deduction is both a safety net and a strategic argument. At tribunal, if you have lost on the procedural points, leading evidence on inevitability of outcome — through the strength of the misconduct evidence, the employee’s prior history, and the clear contractual policy — can significantly limit your financial exposure.

Compensation

Compensation for unfair dismissal has two components.

Basic award: Calculated on the same formula as statutory redundancy pay — age, length of service, and weekly pay (capped at £643). The minimum basic award is £8,533 (for automatically unfair dismissal in certain health and safety and trade union categories).

Compensatory award: Actual financial loss — lost earnings, pension contributions, loss of statutory rights. Capped at the lower of £115,115 or 52 weeks’ gross pay. The cap applies to the total compensatory award and is uplifted periodically. Note: the cap does not apply to whistleblowing claims or health and safety/automatically unfair dismissal claims in certain categories, where compensation is uncapped.

ACAS uplift: Where the employer has failed to follow the ACAS Code of Practice on Disciplinary and Grievance Procedures, the tribunal can increase the total award by up to 25%. This is a real risk in cases where the employer has cut corners procedurally.

Where the employee has contributed to their dismissal by their own conduct, the tribunal will reduce the compensatory award by an appropriate percentage — sometimes substantially. An employee who was genuinely guilty of the misconduct, even if the process was flawed, may recover only a fraction of their losses.

Settlement: When and How

Settlement is often the sensible commercial outcome. Tribunal proceedings are time-consuming for managers, damaging to morale, unpredictable in outcome, and costly. Even a strong employer’s case can go wrong. A well-judged settlement offer at the right stage resolves matters cleanly.

For unfair dismissal (not discrimination), s.111A ERA 1996 permits pre-termination negotiations — “protected conversations” — where the employer can approach the employee with a settlement proposal without that conversation being admissible in tribunal. This is useful where the employer wants to explore a mutually agreed exit before formal proceedings have started. But the protection is limited to unfair dismissal claims only: if discrimination or whistleblowing is also in issue, the conversation may still be admissible on those grounds.

In the classic settlement agreement: the employee receives an enhanced payment in exchange for waiving all claims. The employee must take independent legal advice — the settlement agreement is void without it. The employer typically contributes £350–£500 + VAT towards the employee’s legal costs for signing a standard settlement agreement; more complex settlements may require a larger contribution. Confidentiality obligations, reference terms, and announcement wording should all be addressed in the agreement.

The timing of a settlement offer matters. An offer made early — before the employment tribunal claim is filed, before disclosure and witness statements — costs less and resolves faster. An offer made after two years of litigation costs much more, even if the eventual settlement figure is similar, because the management time, legal costs, and distraction have already been spent.