Constitutional Court Judgment of 17 July 2025: first nail in the coffin of the Belgian Private Investigation Act?

Less than a year ago, on 16 December 2024, the Belgian Private Investigation Act entered into force. It represented a landmark reform for the conduct of private investigations in Belgium, more widely known as corporate investigations.

The Act repealed the outdated 1991 statute, which had been aimed primarily at private detectives, and introduced a new legal framework targeting private investigation in a broad sense, whether carried out by a licensed detective or private investigations company or, in an inhouse set‑up, by a fraud detection team or another department responsible for internal investigations.

Despite providing a fairly comprehensive legal framework — including, for example, detailed rules on how private investigations are to be conducted, such as the right of an interviewee to be accompanied by a counsel of their choice — the Act remains particularly uncertain in several respects, beginning with its scope of application.

Indeed, the quality of the legislative drafting varies greatly from one provision to another. It therefore comes as no surprise that a first section of one of its articles has now been annulled by the Belgian Constitutional Court.

Barely four days after the Act entered into force, on 20 December 2024, an application for annulment was lodged. In the case leading to the Court’s judgment of 17 July 2025, a former police commissioner challenged the Act as discriminatory. The Act prevented her from delivering training on private investigations because she had left the police force less than three years earlier (Article 30, paragraph 1(6)), whereas a serving police officer could deliver such trainings (under an exception provided in Article 30, paragraph 4).

After an in‑depth review, the Constitutional Court held that the difference in treatment between these two situations was not reasonably justified. It therefore annulled Article 30, paragraph 4 of the Act.

While the subject matter of this annulment may appear anecdotal, it reflects a broader reality likely to resurface in the future: many of the Act’s shortcomings may not withstand constitutional review. It is therefore essential to closely monitor developments in this legislative framework, which will likely evolve in response to future court rulings.

Our experts are available to provide you with the clarity regarding this Act and to ensure close monitoring of its evolution.