Internal investigations in the workplace: are you ready for 16 December 2026?

When do internal investigations fall under the Private Investigation Act?

The Private Investigation Act uses the term ‘private investigation’. This might suggest that the legislation only applies to investigations conducted by external private investigators. However, this is not the case.

Even an occasional internal investigation involving one of your own employees may fall within the scope of the Act. For example, this may be the case when you, as an employer, want to determine whether an employee has:

• violated internal rules;

• misused confidential information;

• engaged in other forms of misconduct.

You do not need to engage an external investigator or have a separate internal investigation department. The Private Investigation Act may also apply when your HR department investigates an incident itself.

Under specific conditions, HR staff are exempt from the authorisation and identification requirements when conducting incident investigations involving employees on behalf of their own employer. However, the other applicable provisions of the Private Investigation Act generally remain in force.

Are you planning to conduct a targeted investigation into suspected employee misconduct? Do not automatically assume that the Private Investigation Act does not apply.

Which obligations already apply to internal investigations?

The Private Investigation Act entered into force on 16 December 2024. If you conduct an internal investigation involving an employee that falls within the scope of the Act, you must already comply with the applicable legal requirements. These requirements cover, among other things, the preparation, conduct and documentation of the investigation.

In particular, you must assess:

• whether there is a legitimate interest justifying the investigation;

• what information you are permitted to collect;

• which investigative activities are allowed;

• how the findings must be documented afterwards.

These obligations also apply when your HR department investigates the incident itself.

Please note: until the end of the transitional period, the sanction of nullity for failing to have the mandatory policy in place does not, in principle, apply yet. However, you must already comply with all other applicable provisions of the Private Investigation Act.

What must you have in place by 16 December 2026?

When an internal investigation concerns one of your own employees, the Private Investigation Act requires a prior and transparent policy. This policy must explicitly state that such investigations may take place within your company. It must also set out the procedures governing workplace investigations.

Employers were given two years from the entry into force of the Act to comply with this requirement.

This transitional period ends on 16 December 2026. By that date, the required policy must therefore be in place if you wish to conduct investigations involving your own employees.

What should an internal investigation policy include?

The Private Investigation Act does not specify exactly which provisions the policy must contain. However, the document must clearly and transparently state that investigations involving employees are permitted and explain the rules that apply.

In practice, your policy may provide clarity on the following aspects:

• Grounds for an investigation: under what circumstances can an internal investigation be initiated?

• People involved: who is authorised to conduct the investigation, and which departments may be involved?

• Procedures: how is an internal investigation organised?

• Permitted investigative activities: which actions are allowed within the limits of the Private Investigation Act, the General Data Protection Regulation (GDPR) and other applicable legislation?

• Employee rights: what rights does the employee concerned have during the investigation?

• Potential consequences: what actions or consequences may follow from the investigation's findings?

It is important that this policy reflects how your company handles incidents and internal investigations in practice. After all, a generic policy offers little practical guidance if it does not clearly define who is responsible for what within your organisation and which steps must be followed when a specific incident occurs.

Why should you prepare for internal investigations in advance?

When an incident occurs, you often need to act quickly. At the same time, the Private Investigation Act imposes various formalities and documentation requirements. Depending on who conducts the investigation and how it is carried out, these may include:

• an investigation assignment or register of assignments;

• an investigation file;

• records of certain investigative activities;

• a report detailing the findings.

By establishing clear procedures and agreements in advance, your company will know which steps to take when an incident occurs.

Proper preparation is also more than just an administrative exercise. The legal value of your investigation findings may depend on it. If the findings are subsequently presented before a court, the judge will examine whether they were obtained in accordance with the Private Investigation Act. Based on this assessment, the judge will determine their evidential value.

The law is particularly strict regarding the mandatory policy. The requirement to establish a transparent framework in advance is prescribed under penalty of nullity. Once the transitional period has ended, an investigation involving an employee that is conducted without the required prior policy may be declared null and void. As a result, the investigation findings may be disregarded for legal purposes. This can have significant consequences, particularly if you intend to use those findings as evidence of serious cause justifying dismissal.

Do not wait until an incident occurs. Make sure you have both the required policy and a practical internal investigation procedure in place well in advance.

How can Vandelanotte help you prepare for 16 December 2026?

Do you want to ensure that your company is fully prepared for the obligations under the Private Investigation Act?

Vandelanotte can help you get ready in time for 16 December 2026. Our specialists can draft the required policy and, where necessary, supplement it with practical procedures and template documents for internal investigations.

This will provide you with a clear and workable framework, ensuring that you know exactly which steps to take when an incident occurs.