Private Investigations Act Series: An Introduction to the New Legal Framework for Internal Investigations in Belgium

What You Need to Know

Key takeaway #1
A new legal framework — the Private Investigations Act broadly governs private investigation activities relating to issues such as suspected fraud, HR incidents, data leaks, and potential misconduct. Companies are required by the Act to adopt appropriate internal regulations before 16 December 2026.
Key takeaway #2
The stakes are high – non-compliance may render any evidence collected null and void: legally robust investigative practices are not just advisable, they are crucial.
Key takeaway #3
The first in a dedicated series of client alerts — upcoming client alerts in this series will cover, among others, scope, obligations, permitted acts, GDPR and sanctions.

Client Alert | 3 min read | 09.15.26

Until recently, Belgian law did not have a general regulatory framework for internal investigations. Companies wishing to conduct an investigation had to navigate a fragmented set of rules that covered general principles and, to a limited extent, privacy and employee rights. The application of these rules to internal investigations was not clear, and it was therefore often difficult to put the rules into practice. This legal vacuum created significant risks, both for the integrity of the investigation itself and for the admissibility of any evidence gathered.

The Private Investigations Act of 8 May 2024 (PIA), which entered into force on 16 December 2024, fundamentally changes that landscape. Rather than merely regulating the profession of the "private detective", the PIA establishes a broad and comprehensive framework governing private investigation activities as a whole — one that applies to external service providers and in-house teams alike.

This reform reflects a broader shift in the current business environment. Internal investigations have become a growing imperative for companies of all sizes, driven by increasing regulatory requirements, heightened expectations around integrity and transparency, and an ever-present need to protect corporate reputation. Whether triggered by suspected fraud, HR incidents, data leaks, or potential misconduct, businesses are more frequently called upon to investigate swiftly and thoroughly — while remaining within the boundaries of the law. The PIA now sets the legal standard against which every such investigation will be measured.

As subsequent alerts in this series will explore in detail, non-compliance carries serious consequences: from administrative sanctions to a prohibition on the use of unlawfully obtained evidence in judicial proceedings. A clear understanding of what the PIA requires — and when it applies — is therefore essential for any organization that conducts, commissions, or relies upon internal investigations in Belgium.

What Immediate Action Should Your Company Take?

Although our upcoming alerts will provide you with detailed guidance on specific topics (see below), there are some immediate steps that all businesses operating in Belgium should consider without delay:

Assess how the PIA applies to your organization. For example, in the case of suspected fraud by employees, your business may rely on an external specialized service provider, on its own internal investigation service, or — for investigations related to its own employees and personnel incidents — on its HR department. Each of these entities are subject to different requirements under the PIA.

Begin to work on your internal investigation policy. Under Article 65 of the PIA, whenever the individual concerned is an employee of the principal, the investigator may only accept a private investigation assignment if the authorization to conduct the investigation and the detailed rules governing private investigations in the workplace are explicitly and transparently set out in a "regulation". This requirement applies regardless of who conducts the investigation (i.e. external company, internal service or HR department). Companies have until 16 December 2026 to adopt this regulation.

Review your investigation team and assess your authorization requirements. Under Article 7 of the PIA, any company or internal investigation service must obtain prior ministerial authorization before conducting any private investigation activity. Under Article 43, each investigator must hold an identification card. Both are valid for five years and renewable. HR departments investigating their own employees in personnel incidents are exempt from both requirements under Article 43, though they remain subject to the PIA’s substantive rules. Keep in mind that those authorized to dismiss or sanction should generally be excluded from the investigative team to protect the three-working-day serious cause dismissal time period.

Seek legal advice before launching any investigation. The PIA is a public order law, and its procedural requirements apply from the very first step. Errors made at the outset of an investigation could result in the entire investigation being declared null and void.

Upcoming Client Alerts

Over the coming months, Crowell & Moring's Brussels team will publish a series of dedicated client alerts to guide businesses and their legal advisers through all key aspects of the PIA. Each alert will address a distinct topic and provide practical, actionable guidance.

The series will cover the following topics: