Prior Declaration of Works: When the Mayor's Silence Constitutes Authorisation

You have submitted a prior declaration for a small extension in Mimizan. Weeks pass, no news from the planning department. After a month, you wonder: can I start the works? The answer is yes, but with caution. This decision of the Court of Cassation of 23 November 1994 confirms it: the mayor's silence constitutes tacit authorisation. A simple rule, but one that can trap impatient owners.

Imagine: in Parentis-en-Born, you want to install a swimming pool or a garden shed. A prior declaration is compulsory, but planning permission is not required for these small structures. You submit your file, and if the mayor does not object within thirty days, you are entitled to carry out your works. This is what the Court of Cassation ruled, reminding that the administration cannot remain silent indefinitely.

But beware: this tacit authorisation is not a blank cheque. It assumes that your declaration is complete and complies with planning rules. Otherwise, you risk a fine and, worse, demolition. Let us decipher this landmark decision and its practical implications.

The Facts: A Story Like Many Others

Mr X, an owner in Mimizan, decides to carry out construction works without applying for planning permission, thinking they are simple exempted improvements. He submits a prior declaration, but does not follow the rules: he starts the works before the one-month opposition period has expired. The town hall reacts and prosecutes him for carrying out works without a valid prior declaration.

Convicted at first instance, Mr X appeals. The Rouen Court of Appeal, in a judgment of 24 January 1994, finds him guilty: he carried out construction works without a valid prior declaration. The judges sentence him to a fine of 2,000 francs (about 300 euros) and order the demolition of the irregular constructions. A severe sanction, showing that lack of authorisation is not forgiven.

Mr X then appeals to the Court of Cassation. He argues that his prior declaration amounted to authorisation, due to the mayor's failure to object within the legal period. The Court of Cassation, in its judgment of 23 November 1994, quashes the appeal decision: it considers that the court did not sufficiently justify its decision. Indeed, according to Articles L. 422-3 and L. 480-5 of the Planning Code (texts governing the regime of prior declarations and criminal sanctions), the prior declaration is deemed authorised if the mayor does not object within one month. The Court of Appeal should have checked whether this period had elapsed before convicting Mr X.

The Reasoning of the Court — Analysed

The Court of Cassation, the highest French judicial court, does not judge the facts but checks whether the law has been correctly applied. In this case, it censures the Court of Appeal for not examining whether Mr X's prior declaration had been objected to within the one-month period. However, Article L. 422-3 of the Planning Code (which sets out the regime for prior declarations) provides that constructions or works exempt from planning permission are subject to a prior declaration, and that in the absence of opposition within one month, this declaration constitutes authorisation. This is known as 'silence amounting to acceptance'.

In other words, the legislator wanted to prevent citizens from being blocked by the administration's inertia. If the town hall does not respond within thirty days, the owner can legitimately consider that they have the green light. But beware: this tacit authorisation is only acquired if the declaration is complete and compliant. If a defect is discovered later, the town hall can still bring criminal proceedings or order demolition, as Article L. 480-5 (criminal sanctions for planning infringements) reminds us.

In this case, the Court of Appeal had found Mr X guilty without checking whether the opposition period had expired. Serious mistake: if the mayor had not reacted within one month, Mr X was in compliance. The Court of Cassation therefore quashes the judgment and sends the case back to another court. In doing so, it reaffirms a protective principle for owners: the administration's silence cannot be used as a weapon against them.

What This Changes for You — Practically

For owners who submit a prior declaration, this decision provides legal certainty. You submit your file to the town hall of Mimizan or Parentis-en-Born, you wait one month, and if no opposition, you can build. But beware: this is not a blank cheque. If your declaration is incomplete or the works are non-compliant, the town hall can still intervene later. For example, if you build a 20 m² conservatory in Parentis-en-Born without respecting boundary distances, you risk a fine and demolition.

For tenants, be vigilant: if your landlord carries out works without a prior declaration, you could suffer nuisance or risk demolition. Check that the authorisations are in order before giving your consent.

For buyers, during a property sale, demand a copy of the prior declaration and the tacit authorisation. If the seller has built without authorisation, you could be held responsible for the irregular works after purchase. undefined, I have come across cases where buyers had to demolish an unauthorised extension at their own expense. A nightmare to avoid.

Finally, for property professionals, this case law confirms that the one-month period is mandatory. If you advise a client, remind them not to start works before this period, even if the town hall seems favourable. Concrete example: a 5 m² garden shed in Mimizan requires a prior declaration; if you start works after 15 days, you are in breach. Better to wait the full 30 days.

Four Tips to Avoid This Type of Dispute

• Submit a complete prior declaration: Before any small project (extension < 20 m², swimming pool, shed), fill in the Cerfa form n°13703*07 and attach all required documents (site plan, layout plan, photos). An incomplete declaration may be rejected and the period does not start.
• Wait strictly one month before starting works: Even if the mayor tells you 'yes' orally, do not start before the legal period expires. The town hall's stamp on your receipt is proof. In Parentis-en-Born, an owner started works on the 25th day: the town hall issued a refusal on the 30th day, and he had to demolish everything.
• Keep the deposit receipt carefully: This is your proof of the date of submission. In case of dispute, this document establishes that you followed the procedure. Have it registered with a number and a stamp.
• Check local planning rules: The local planning plan (PLU) of your municipality may impose additional constraints: height, appearance, distances. In Mimizan, some coastal areas are protected. Consult the planning department before submitting your declaration.

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Further Reading: Related Case Law and Developments

This 1994 decision is part of a consistent line of the Court of Cassation. For example, in a judgment of 6 October 1993 (n° 92-85.112), the Court had already held that the mayor's silence for one month constituted tacit authorisation for a prior declaration. More recently, the Council of State, in a decision of 13 July 2016 (n° 390781), specified that this tacit authorisation can be withdrawn within three months if it is illegal, but only on legality grounds. An additional safety margin for the administration.

The courts' tendency is therefore to protect the citizen against the administration's inaction, while maintaining the possibility of ex post controls. For the future, recent reforms (Order of 23 October 2013) have extended the principle of silence amounting to acceptance to many administrative procedures. But in planning, the one-month period remains the rule for prior declarations. Be careful though: if your project requires planning permission, the mayor's silence constitutes a refusal after two months. Do not confuse the two regimes.

What You Must Absolutely Remember

FAQ:

1. Can I start my works before the end of the month after submitting a prior declaration? No, wait until the 31st day. Otherwise, you are in breach.
2. What if the town hall has not responded after one month? You can start the works, but keep the receipt. To be sure, request a certificate of non-opposition (free) from the town hall, which formalises the tacit authorisation.
3. What are the risks if I build without a prior declaration? Fine up to €120,000 (Article L. 480-4 of the Planning Code) and demolition ordered by the court. In Parentis-en-Born, an undeclared swimming pool cost its owner €15,000 in demolition costs.
4. What if my prior declaration is refused? You can challenge the refusal before the administrative court within two months. Or modify your project to make it compliant.
5. Does this rule apply everywhere in France? Yes, the Planning Code is national. But each municipality may have stricter rules in its PLU. Always check locally.

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