Internal investigations: what employers need to know
My name is Emmanuel Wauters, and I am a partner at Clarity Legal, a law firm specialising in all areas of HR law, labour law, HR taxation and social security, as well as internal investigations.
Internal investigations are governed by a fairly recent law, dating from 18 May 2024: the Belgian Act on Private Investigation. This law replaces the former legislation on private detectives but has a much broader scope. As a result, it can have significant consequences for most players in the business world and, in particular, for employers and organisations.
The reason is simple: the Act governs internal investigations.
When may an internal investigation be necessary?
Employers and organisations can quickly find themselves in situations where an internal investigation becomes necessary.
This may be the case when an employer is faced with potential fraud committed by an employee or a situation where theft may have been committed by an employee. But it goes much further than that.
An internal investigation may also become necessary when an employer receives a report concerning the potential existence of harassment or discrimination within the company, or in the context of a serious workplace accident where the circumstances of the incident need to be analysed.
In these situations, the employer will not only have the possibility but often also the obligation to analyse the situation, examine the circumstances and gather all the relevant elements.
This is particularly important in the context of harassment. The Workplace Well-Being Act of 4 August 1996 provides that, once an employer becomes aware of a situation that could potentially amount to harassment, it is obliged to take appropriate measures to put an end to it.
However, before deciding which measures are appropriate – for example, removing an employee from a particular work situation or issuing a warning – the employer first needs a full understanding of what happened.
This means hearing the employees involved: the person claiming to be the victim of harassment, the person accused of committing it and, where appropriate, witnesses who may have observed the alleged conduct.
These are typical elements falling within the notion of internal or private investigation as defined by the Act.
The same applies in the case of potential theft. Suppose an employee is suspected of having taken money from the till and another employee reports this to the employer. The employer may consider terminating the employee's contract for serious cause. Before doing so, however, it will first need to gather the relevant facts and obtain what case law commonly refers to as certain and sufficient knowledge of the situation.
Here too, this may require interviewing the person accused of theft, the person who reported it and any witnesses who may have observed what happened.
Internal investigations can therefore have a broad impact on the way human resources are managed within a company.
The Act of 18 May 2024 and the notion of private investigation
The Act of 18 May 2024 is an extremely formalistic piece of legislation.
It first defines the notion of private investigation. Private investigation is defined as an activity aimed at collecting information or evidence concerning other persons, carried out by a person on behalf of another person in order to protect the interests of the person commissioning the investigation.
When a company instructs someone to carry out investigative acts internally, this may therefore fall within the definition of private investigation laid down by the Act.
Another important principle is that a private investigation service, whether internal to the company – such as a compliance or audit department – or external, typically a private detective agency, must in principle hold a licence issued by the Ministry of the Interior.
Obtaining such a licence requires compliance with a fairly formalistic procedure.
There are, however, exceptions. One of these concerns HR departments. When an HR department is tasked with carrying out acts of internal investigation, it does not need to hold the licence issued by the Ministry of the Interior.
A strict framework for internal investigations
The Act also provides that acts of private investigation and internal investigation must be conducted within a fairly strict framework.
The main purpose of this framework is to protect the interests and rights of the person being interviewed by the employer or its representative during the investigation.
The most common investigative act in an internal investigation is the interview. This may involve interviewing the alleged victim, the alleged wrongdoer, witnesses or other persons concerned.
For these interviews, the Act provides a strict framework intended to protect the rights of the person being interviewed.
Before beginning the interview, the interviewer must inform the person of the rights granted to them by law. In particular, the person must be informed that they are not required to answer every question asked and that they are not required to sign the report of the interview.
The person must also be informed of the context in which the interview is taking place. For example, they may be informed that a person within the company has been accused of fraud or theft and that this is the reason why the internal investigation is being conducted.
The person must therefore be informed of their rights before the interview begins.
At the end of the interview, an individual report must also be prepared, setting out the questions asked and the answers provided regarding the facts and circumstances discussed during the interview.
The importance of neutrality and objectivity
Although the Act does not provide overly detailed guidance on the types of questions that may be asked during an interview, certain good practices should be followed.
When conducting an internal investigation, it is important to act with complete neutrality.
An investigation will generally start because a report has been made concerning possible fraud, theft, harassment or discrimination. Nevertheless, the objective of the person conducting the investigation should be to gather all relevant elements, preferably both those that may be against and those that may be in favour of the person concerned.
This is not necessarily an easy exercise, particularly when the investigation is carried out internally by someone employed by the company and who normally acts in the company's interests. During the investigation, however, that person must, so to speak, change hats and approach the matter with neutrality.
While this is not necessarily an explicit requirement imposed by the Act of May 2024, it can become extremely important if a dispute subsequently arises.
For example, if an employee challenges a dismissal decided by the employer following the investigation, a court will consider not only whether the formal requirements of the Act were complied with – whether a licence was required, whether the person was properly informed of their rights – but also the circumstances in which the investigation and interviews were conducted.
The credibility, neutrality and objectivity of the investigation may therefore also be assessed by reference to the nature of the questions asked.
For that reason, it is important to think carefully, before launching an internal investigation, about the questions that will be put to the various people involved.
There is no requirement to ask everyone the same questions. The questions asked of an alleged victim will naturally differ from those put to the person accused of the conduct under investigation.
What matters is that the questions are formulated in a way that allows the person being interviewed to give their own version of events. Questions should not be formulated in a way that steers the answers in favour of the employer.
Open-ended questions are therefore particularly important.
It can also be useful to conclude an interview by asking whether the person believes that there are other facts that should be brought to the employer's attention or whether other people should be interviewed as part of the investigation.
An internal investigation is an evolving process
An internal investigation must be seen as something evolving.
When facts are first reported and an employer decides to launch an investigation, it will identify the people who need to be interviewed. Usually, the potential victim and the person who allegedly committed the acts will already be known. The victim may also identify other people who could provide relevant information.
However, as the investigation progresses, new information may emerge.
It may become apparent, for example, that a person initially accused of workplace harassment may also have committed theft. It may also become clear that, in addition to the witnesses initially identified, other people witnessed the alleged acts.
The employer may therefore decide to broaden the scope of the investigation and interview additional people identified during the process.
This brings us to another important issue: the timing of the investigation.
Timing and dismissal for serious cause
Timing is particularly important when the employer is considering dismissing an employee for serious cause.
Dismissal for serious cause is strictly governed by the Employment Contracts Act. In particular, dismissal must take place within three working days from the date on which the person authorised to dismiss acquired certain and sufficient knowledge of the facts.
Does this mean that an employer must immediately dismiss an employee for serious cause as soon as another employee reports that a colleague has stolen from the till or committed acts of harassment?
No.
Case law accepts that, once an employer has suspicions regarding the possible existence of facts that could justify dismissal for serious cause, the employer is entitled to conduct an investigation.
The question then becomes one of timing.
If the three-working-day deadline is not respected once the employer has acquired certain and sufficient knowledge of the facts, the dismissal for serious cause may be considered irregular. The dismissed employee could then claim notice pay, regardless of whether the underlying facts are ultimately established.
Case law relating to internal investigations accepts that an employer may conduct an investigation – and that it is advisable to do so before taking measures against an employee – but also requires that the investigation be conducted within a reasonable period.
There is no fixed definition of what constitutes a reasonable period. It is not automatically two days, five days or one week. Whether the requirement has been respected will depend on the specific circumstances of the case and will ultimately be assessed by the court.
For example, an employer may be confronted with allegations of harassment involving ten potential victims. In such circumstances, it may be appropriate to interview all ten rather than limiting the investigation to one person.
It may also be advisable to interview people who do not claim to be victims in order to maintain as broad, credible and neutral an approach as possible.
This will naturally affect the duration of the investigation.
The same may happen when key witnesses are unavailable, for example because they are on holiday. In such circumstances, it may be necessary to wait for their return before continuing and closing the investigation.
The important point is to anticipate the possibility that the person concerned may later challenge the decision taken against them before a court.
The employer must therefore be able to demonstrate not only whether the facts were established, but also that the investigation was conducted seriously and that everything necessary was done to carry it out and close it within a reasonable period.
Individual reports and the final investigation report
The formal requirements do not stop with the interview itself.
At the end of each interview, an individual report must be prepared. The draft report must then be submitted to the person interviewed, who must be given the opportunity to correct its contents.
Once all relevant persons have been interviewed and the investigation has been closed, a final report must also be prepared.
This final report will be submitted to the person within the company responsible for deciding whether action should be taken following the investigation.
For example, an HR department may conduct the investigation and prepare individual reports, which will subsequently be compiled into an overall report. That overall report may then be submitted to the company's management, which will be responsible for making the final decision concerning the persons involved.
Failure to comply with the Act and the risk of nullity
One of the most significant aspects of the legislation is its highly formalistic nature.
The Act provides that where certain formal requirements have not been complied with, evidence gathered during the internal investigation may be considered null and void.
The Act is a matter of public policy, meaning that its principles cannot simply be departed from.
In practical terms, if the requirements concerning the rights of interviewees, individual reports or the final report have not been complied with, or if an investigation has been carried out by an internal audit department without the required licence from the Ministry of the Interior, the evidence gathered may be considered null and void.
If a dispute subsequently arises – for example, regarding a dismissal for serious cause – a court may therefore disregard evidence gathered in breach of the Act of 18 May 2024.
The 16 December 2026 deadline
Another important requirement concerns the transitional period provided for by the Act.
The Act entered into force in December 2024 and the transitional period ends on 16 December 2026.
By that date, any company or organisation that may potentially need to carry out acts of private investigation – including internal investigations – must have internal regulations on private investigation in place.
This obligation applies regardless of the nature of the company's or organisation's activities and regardless of the number of employees it has.
The internal regulations must provide an overview of the circumstances in which acts of private investigation may be carried out.
They must also specify who may conduct such acts: the HR department, internal audit, compliance, an external service or potentially a lawyer.
The regulations must further set out the measures that may potentially be taken against the employees concerned and explain the rights of those employees.
From 16 December 2026 onwards, if a company needs to carry out an internal investigation without having the required internal regulations in place, this may lead to the nullity of the evidence gathered during the investigation.
This is therefore an important point for companies to address as part of their HR management before the end of 2026.
Any organisation may potentially find itself in a situation where an internal investigation becomes necessary, whether because of fraud, theft, harassment, discrimination or a workplace accident.
The role of lawyers in internal investigations
The Act has a broad scope and applies to acts of private investigation carried out by investigative services, whether internal or external.
However, certain professions are excluded from its scope. This is notably the case for lawyers.
Lawyers are, in principle, not subject to the scope of the Act of 18 May 2024.
Since June 2026, the Dutch-speaking Bar Association has also confirmed that lawyers may carry out acts of private investigation without necessarily being required to comply with the conditions laid down by the Act, provided that these investigative activities fall within the scope of their legal advisory work.
A lawyer cannot, of course, present themselves as a private detective or operate a parallel private-detective business. However, in the context of legal advisory work for clients, lawyers may carry out private investigation activities on their clients' behalf.
It is in this context that Clarity Legal launched enquêteinterne.be in French, interneonderzoeken.be in Dutch and workplaceinvestigations.be in English.
These websites are exclusively dedicated to internal investigations and provide an overview of the applicable regulations, particularly the Act of 18 May 2024, as well as the ethical rules applicable to lawyers carrying out such work.
Lawyers carrying out internal investigations are subject to a strict code of conduct, including principles relating to independence, specialisation and respect for the rights of all parties involved.
Why involve a lawyer in an internal investigation?
The added value of involving a lawyer does not simply lie in the fact that lawyers are, in principle, not required to comply with all the conditions imposed by the Act of 18 May 2024.
When conducting an internal investigation, we nevertheless comply with the safeguards concerning the rights of the persons involved. This includes preparing individual reports and an overall investigation report.
The added value also lies in the legal reflexes developed through experience with procedural matters and, in particular, disputes and dismissals for serious cause.
As lawyers, we know which elements are likely to matter before the courts, which elements courts take into account and which elements they may disregard.
This allows us to approach an investigation through a legal lens from the outset.
There are therefore two possibilities: the lawyer may conduct the investigation independently on the basis of a mandate given by the employer, or the lawyer may assist the employer while the employer conducts the internal investigation itself.
Both approaches are possible.
More information on internal investigations and the applicable legal framework is available on our dedicated website, enquêteinterne.be / interneonderzoeken.be / workplaceinvestigations.be.