When a grievance is a warning sign: lessons for employers

For many employers, a grievance arrives with a sense of inevitability. The formal complaint lands in HR’s inbox, meetings are scheduled, statements are taken, and attention turns to bringing the matter to a conclusion as quickly as possible.

Although there is no single piece of legislation that sets out how employers must handle grievances, Employment Tribunals expect employers to follow the Acas Code of Practice on Disciplinary and Grievance Procedures. A failure to do so can result in tribunal compensation being increased by up to 25%.

It is easy to fall into the trap of treating the grievance itself as the issue to be fixed. In reality, a formal complaint is often only the visible symptom of something deeper within the business. That is why employers should use grievances not just to resolve an individual dispute, but to understand what they may reveal about management, culture, and communication.

What grievances can tell you about your business

In practice, grievances arise for all sorts of reasons. Sometimes a manager has allowed a workplace disagreement to drift on for too long. Sometimes communication has broken down. In other cases, an employee may feel that concerns they have raised informally have never been properly addressed. Whatever the trigger, the grievance itself is often only one part of a much longer story. It is not uncommon to investigate a grievance about a single incident only to discover that the formal complaint is not the full story and that there has been a pattern of concerns stretching back many months. By the time an employee decides to raise a formal complaint, there has usually been a series of conversations, frustrations, or misunderstandings that management may never have been aware of and the underlying issue has often been developing for some time.

An employee complaining about favouritism may actually be highlighting poor management practices. A dispute between colleagues may reveal wider cultural tensions within a team. Repeated complaints about workload could indicate organisational problems that are affecting retention, wellbeing, and productivity.

Most people do not relish making formal complaints about their employer. Raising a grievance can be uncomfortable, time-consuming, and professionally daunting, particularly where the complaint concerns a manager or senior colleague. A grievance not only gives employers an opportunity to resolve the obvious issue raised in the grievance, but also allows an employer to spot trends and identify deeper issues that might sit beneath the complaint before they become more serious and more costly to address.

The legal risk often sits beneath the complaint

Employment lawyers frequently see cases where a grievance that appeared relatively straightforward turn out to involve allegations of discrimination, whistleblowing, or constructive dismissal once the facts are explored in more detail. Sometimes the employer only realises this when an employee takes a claim to Tribunal, and the grievance is scrutinised as part of the evidence.

Employers are arguably more likely to overlook the legal risk now that employees are using AI to formulate their grievances. Grievances tend to be longer, more complicated, and it is often difficult to get to the crux of the issue, let alone the legal risk surrounding it. Take the example of an employee who submits a four-page letter complaining about their manager alleging, amongst other things, that the manager regularly excludes the employee from meetings. At first glance, it may appear to be a straightforward workplace disagreement or personality clash. During an investigation, however, the employee mentions his sexuality and alleges bias. Suddenly, the business is no longer dealing with a simple grievance; it may be facing allegations of discrimination, harassment, or victimisation.

Similarly, complaints about treatment following a grievance can quickly evolve into a victimisation claim or an employee asking for flexible working can sometimes become a disability discrimination claim if that flexibility might be considered a reasonable adjustment, while grievances about unreasonable managerial conduct often form part of later constructive dismissal allegations.

For employers, the key point is that a grievance should never be assessed solely by reference to the words written in the complaint. They should also consider what legal and organisational risks might sit behind them.

Warning signs employers should not ignore

Certain themes appear again and again in grievances. One is repetition. If concerns are repeatedly raised about the same individual, team or practice, employers should take notice. Another is timing. Complaints that arise shortly after disciplinary action, performance management discussions, or organisational change can indicate wider tensions. Employers should also pay attention to signs of defensiveness from managers, and to complaints involving senior managers where employees may have previously been reluctant to speak up; this is especially important given the upcoming change to the law requiring employers to be proactive and take all reasonable steps to prevent sexual harassment.

When good employers get grievances wrong

Most employers understand that grievances need to be investigated. Problems usually arise not because complaints are ignored altogether, but because the process is approached with the wrong mindset.

Sometimes there is an overwhelming desire to close matters quickly. In other cases, managers become too focused on defending previous decisions, or the investigation is shaped by an assumed outcome. Employees are usually quick to spot when a process lacks genuine independence or openness. Once trust is lost, the risk of escalation increases significantly.

That is why grievances should not be seen as purely HR or procedural matters. Formal complaints often expose problems that have been sitting beneath the surface, whether that is inconsistent management, poor communication, or unresolved tensions within a team. Why did the employee feel they had to use a formal process? Were earlier opportunities to resolve the issue missed? Do managers have the confidence and training to handle difficult conversations?

Focusing solely on whether a grievance is upheld risks missing the point. Even where a complaint is rejected, the process may reveal weaknesses in management, communication, or workplace culture that still need attention.

What employers should do after the grievance decision

The end of the grievance process should not be the end of the employer’s thinking about the issues raised. Employers should instead move quickly from outcome to action. That may include reviewing how managers communicate decisions, whether policies are understood in practice, whether concerns were missed at an earlier stage, or whether similar issues could arise elsewhere in the organisation. Even where no wrongdoing is found, the grievance may still point to a breakdown in trust, a lack of clarity, or a management issue that needs attention.

In some cases, relationships will need rebuilding; in others, managers may need support or additional training. Sometimes the process reveals weaknesses in policies or working practices that were not obvious beforehand. The real value often comes from what happens after the decision has been made.

Key takeaways for employers

• Do not treat the written grievance as the whole issue; consider what may sit behind it.
• Look for patterns, particularly repeated concerns about the same manager, team, process, or behaviour.
• Keep an open mind and ensure investigations are genuinely independent and objective.
• Consider whether the grievance raises wider legal risks, such as discrimination, whistleblowing, or constructive dismissal.
• Use the outcome to take practical follow-up action and improve management practices or workplace culture, regardless of whether the complaint is upheld.

If your organisation is dealing with a sensitive workplace grievance, or you are concerned that complaints may point to wider workplace risks, obtaining advice at an early stage can help you manage the process effectively, identify legal exposure, and avoid issues escalating into formal disputes or tribunal claims.

For support with workplace grievances, investigations, or wider employee relations issues, please contact Employment partner Asha Kumar and Employment senior associate Velma Eyre.