The Constitutional Court rules that Article 30 of the Wallo…

The Constitutional Court ruled, in judgment no. 50/2026 of April 23, 2026, that Article 30, § 1, paragraph 1, 2°, of the Walloon Region decree of March 1, 2018 “relating to the management and remediation of soils” violates Articles 10 and 11 of the Constitution. The extract of this judgment, bearing reference C − 2026/006342 and docket number 8422, is published in the Belgian Official Gazette of October 20, 2026, p. 56642.

Origin of the case

The Court was seized of a preliminary question posed by the Council of State in judgment no. 261.974 of January 14, 2025, the notification of which reached the registry on January 28, 2025. The Council of State asked whether the disputed provision, read in combination with the polluter-pays principle, established an unjustified difference in treatment between obligation holders who operate their establishment as assignees of an environmental permit and those who are not.

The judgment was rendered by a formation composed of presidents Pierre Nihoul and Joséphine Moerman, judges Thierry Giet, Michel Pâques, Yasmine Kherbache, Sabine de Bethune, Emmanuelle Bribosia, Willem Verrijdt, and Kattrin Jadin, as well as president emeritus Luc Lavrysen, assisted by clerk Frank Meersschaut, under the presidency of Pierre Nihoul.

The derogatory mechanism in question

The decree of March 1, 2018 organizes the cascade of remediation obligations. Article 19 lists the obligations related to soil management:

the orientation study;
the characterization study;
the remediation project;
the implementation of remediation acts and works;
the implementation of monitoring measures;
the implementation of security measures.

In principle, the operator who carried out the orientation study in application of Article 24, § 1, 1°, remains bound by the other obligations in the event of the cessation of their installation (Article 28). Article 30, § 1, paragraph 1, 2°, however, provided for an exemption when the holder demonstrates, following investigations approved by the administration, that the pollution results from the actions of a solvent third party “to the exclusion of the actions of the permit assignor.”

The two grounds retained by the Court

The Court first dismisses the argument of the Walloon Government according to which the assignee and assignor would be contractually linked and therefore not comparable: the contractual link is not sufficient to conclude non-comparability, otherwise the control of the principle of equality would be deprived of substance. Both categories demonstrate the existence of another party responsible for prior pollution; they are therefore comparable with regard to a regime that aims to apply the polluter-pays principle.

The Court then examines the invoked objectives. Preventing an operator from unduly evading their obligations through a permit transfer organized for that purpose is a legitimate objective, but the provision does not contribute to it: exempting the transferor who caused the pollution allows the latter to precisely evade it through a transfer. The same applies to the objective of preserving contractual freedom and the fluidity of real estate and commercial transactions, which the decree pursues through the removal of the alienation of real rights as a triggering event, the formalization of the transfer, and the information obligations of Article 31.

The principles mobilized

The Court relies on the polluter-pays principle as derived from Directive 2004/35/EC of 21 April 2004 on environmental liability, Article 191, paragraph 2, of the Treaty on the Functioning of the European Union, and Article D.3, 2°, of Book I of the Walloon Environment Code. It cites the Commune de Mesquer judgment delivered by the CJEU on 24 June 2008 (C-188/07), according to which the polluter is the one who, through their activity, contributed to the risk of the pollution occurring.

The preparatory works of the Walloon Parliament (2017-2018, No. 984/1) did not, on their own, clarify the objective of the disputed restriction. The Court further notes that the transferee retains the possibility of passing the costs on to the transferor, but that the risk of first bearing the costs of pollution caused by the transferor and discovered ex post facto may delay transactions.

What this changes for site acquirers

The judgment concerns any acquirer of a Walloon industrial site operated under an environmental permit transferred by a previous operator. The transferee who establishes that the pollution originates from the transferor may now avail themselves of the exemption from obligations subsequent to the orientation study, without the polluter’s status as a transferor acting as an obstacle. The decision was rendered in French and Dutch on 23 April 2026, in accordance with Article 65 of the special law of 6 January 1989 on the Constitutional Court.

Source: Moniteur belge, No. 239, 20 October 2026, p. 56642 — Constitutional Court, extract from judgment No. 50/2026 of 23 April 2026, docket 8422, ref. C − 2026/006342.