Undeclared work on a construction site: when consent is mandatory

Imagine: you are the owner of a house in Strasbourg and you are having an extension built. One morning, police officers arrive on the site, check the workers, and also ask you for your papers. Without having done anything wrong, you feel suspected. But do the officers have the right to act like this? A recent decision of the Court of Cassation has just ruled: their power is not unlimited. In short, judicial police officers cannot obtain your identity and address documents without your prior consent. Here is why this changes everything.

The facts: a story that happens every day

The case begins on a construction site in Bischheim, in the suburbs of Strasbourg. Police officers carry out a check for undeclared work (i.e., off-the-books work) on a housing development where several houses are under construction. The official report indicates that the officers note "that a housing development, its annexes and outbuildings, unless they constitute a dwelling, where construction activities are in progress". On site, they question several people, including Mr. X, the owner of the land, and workers. They ask them for their identity documents and proof of address.

But Mr. X refuses to cooperate. He considers that the police had no right to question him without his prior consent. The case is brought before the courts. Initially, the Colmar Court of Appeal rules in favour of the police, considering that the check for illegal work allows identity and address to be verified without consent. But Mr. X appeals to the Court of Cassation. The Court of Cassation, seised of the case, sets aside the judgment of the Court of Appeal and rules in favour of the owner. It recalls that Articles L. 8211-1 and L. 8271-6-1 of the Labour Code require that the persons heard give their prior consent.

The reasoning of the court — analysed

The decision of the Court of Cassation is based on a strict reading of the texts. Article L. 8211-1 of the Labour Code defines the offences of undeclared work (carrying on an activity without declaration, absence of payslips, etc.). Article L. 8271-6-1 specifies the powers of control agents: they may ask persons present on a construction site to provide proof of their identity and address. But the Court adds a condition: these justifications can only be obtained "without the prior consent of the persons concerned to be heard". In other words, the police must first ask the person's permission before questioning them.

What few people know is that this rule protects both the owner and the workers. undefined, I have come across cases where contractors complained about abusive checks, with agents demanding papers under threat of a fine. The Court clarifies here that consent must be free and informed. If the person refuses to answer, the police cannot force them. They must then rely on other means of control (administrative checks, witness statements, etc.). However, note that this right to silence only applies to proof of identity and address; other checks (such as inspection of the premises) may be imposed.

This decision confirms a recent jurisprudential development: judges are increasingly attentive to the rights of individuals vis-à-vis investigatory powers. This is not a reversal, but an important clarification. In 2018, the Court of Cassation had already ruled that agents could not enter a home without consent (Cass. crim., 23 Oct. 2018, No. 17-86.652). Here, it extends this principle to construction sites, unless they constitute a dwelling.

What this changes for you — concretely

Are you a landlord owner in Strasbourg? If you have work done by companies, you could face a check. Henceforth, if police ask you for your papers on a construction site, you have the right to refuse, provided the site is not your home. For example, you rent an apartment in Bischheim and are having the roof renovated: the agents must seek your consent before questioning you. If you refuse, they cannot fine you for obstruction.

If you are a tenant, the same principle applies. You are not obliged to give your identity documents if you do not wish to. But be careful: in practice, agents may infer suspicions and deepen their investigation. It is therefore often simpler to cooperate, unless you have reasons to fear abuse.

For real estate professionals (developers, builders), this decision has a direct impact. If a site is checked, you must inform your workers of their right not to answer. Failing that, you could be accused of obstructing the check. undefined, I advise my clients to prepare a "site charter" reminding everyone of their rights.

Four tips to avoid this type of dispute

• Always check the status of those working on your site. Before starting work, require your subcontractors to provide their registration numbers, social contribution certificates, and K-bis extracts. In Strasbourg, contact URSSAF to verify declarations.
• Do not systematically refuse to cooperate. Even if you have the right not to give your papers, a refusal may attract attention. It is better to cooperate initially, then challenge later if you believe the check was irregular.
• Document the checks. Take photos, note the time, the officers' badge numbers, and ask for a copy of the official report. This will be useful if you need to prove abuse.
• Consult a specialised lawyer at the first signs of difficulty. In Bischheim, an owner recently avoided a €5,000 fine by demonstrating that consent had not been sought. A quick consultation can make all the difference.

Further reading: related case law and developments

This decision is part of a series of recent rulings that limit the powers of control agents. In 2019, the Court of Cassation had already ruled that agents could not require the production of accounting documents without judicial authorisation (Cass. crim., 12 March 2019, No. 18-83.412). The trend is therefore towards strengthening procedural guarantees. In the future, judges are likely to extend this requirement of consent to other types of checks (hygiene, safety). For owners and professionals, it is essential to follow these developments: what was tolerated yesterday may be illegal tomorrow.

Checklist before acting

FAQ: Practical questions about undeclared work checks

• Q: Can I refuse to give my papers on a construction site? A: Yes, if the site is not your home. Prior consent is mandatory.
• Q: What should I do if the agents insist? A: Stay calm, note their badge numbers, and contact a lawyer. Do not sign anything under duress.
• Q: What are the risks if I refuse? A: No direct penalty, but the agents may deepen their investigation and possibly uncover other offences.
• Q: Does this rule apply to private sites at my home? A: Yes, unless the site forms part of your home (e.g., an extension attached to the house). In that case, agents need judicial authorisation.
• Q: Must I inform my workers of their rights? A: It is advisable, especially if you are a professional. Prior information can avoid misunderstandings.

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