Non-compliant building permit: conviction upheld even after regularisation

You have bought a flat in Petit-Quevilly, near Rouen, and your neighbour is carrying out works. Very quickly, you notice that the construction far exceeds what the displayed building permit provided for. You reported it to the town hall, but the building work continues. Then, one fine day, the neighbour obtains a prefectural order that regularises everything. Has he won? Can he escape any sanction?

This is precisely the question that the Court of Cassation decided in 1964. A landowner had built without complying with his permit, had been convicted at first instance, and then obtained from the prefect a dispensation accompanied by a new permit. The Supreme Court said: the conviction remains valid, because the infringement existed at the time of the proceedings. But the demolition, on the other hand, can be reviewed.

This decision, although old, is still applied. It reminds us that regularising afterwards does not make the criminal fault disappear. For landowners, landlords, and property professionals, this is a clear warning: it is better to scrupulously comply with your permit from the start.

The facts: a story that happens every day

Imagine Mr X, a landowner in Dieppe, who obtains in 1961 a building permit for a building. He starts the works, but takes liberties: an extra floor, different openings, non-compliant materials. The neighbour, Miss Y, owner of the adjoining plot, brings the matter before the criminal court. She considers that the overshadowing and loss of view cause her harm.

At first instance, the court convicts Mr X for infringement of the planning code. It also orders demolition under penalty, and awards damages to Miss Y. But Mr X does not give up. He obtains from the prefect of Seine-Maritime an order exempting him from certain building rules, subject to obtaining a new permit. This new permit is issued to him on 11 April 1963. Armed with this regularisation, he appeals.

The Rouen Court of Appeal confirms the criminal conviction but quashes the demolition order. Miss Y appeals to the Court of Cassation. The Court of Cassation must decide: can a permit obtained after the infringement erase the fault?

The reasoning of the court — analysed

The Court of Cassation, criminal chamber, delivers its judgment on 26 February 1964. It distinguishes two aspects: the criminal conviction and the demolition measure.

On the conviction, the Court is firm: 'if it is established that at the time of the proceedings a defendant had built a building without complying with the terms of his building permit, it matters not that after the conviction by the first judges, the said defendant obtained from the prefect an exemption from the application of certain building rules, provided that the prefectural order made the construction subject to the prior obtaining of a new permit.' In other words, the infringement is constituted at the date of the facts. The legal basis is the former Article R. 421-1 of the Planning Code (now codified in Articles L. 421-1 et seq.), which requires a compliant permit. Subsequent regularisation does not have retrospective effect.

However, on the demolition, the Court quashes the appeal judgment. The Court of Appeal could not remove the demolition without explaining the consequences of the prefectural order and the new permit. If the construction is now compliant with the new rules, demolition could be disproportionate. The Court therefore refers the case back for a new judge to examine this point.

This decision confirms consistent case law: the criminal judge assesses legality at the time of the facts. This is a principled position that protects planning public policy. It is neither a reversal nor an evolution, but a classic application of criminal planning law.

What this changes for you — concretely

Are you a landowner and have you built without complying with your permit? Do not count on a late regularisation to escape a criminal conviction. The fine can reach €120,000 (Article L. 480-4 of the Planning Code), and the judge may order restoration of the premises. Even if you obtain a modified permit afterwards, the initial violation remains punishable.

For a buyer, this is an alarm signal: if you buy a property whose construction was disputed, you could inherit a demolition action. For example, in Dieppe, a developer built a 12-unit residence with one more floor than the permit. The co-owners were ordered to demolish the top level, a loss of €800,000. The regularisation obtained by the developer afterwards did not erase the fault.

If you are a neighbour of an illegal construction, this decision supports you: you can take legal action even if the builder regularises afterwards. But beware, demolition is not automatic. The judge may consider that the regularisation makes the construction compliant and refuse demolition. So you must act quickly, at the first signs of infringement.

Four tips to avoid this type of dispute

• Before starting work, check your permit. Compare the permit plan point by point with the actual project. If you need to change something, apply for a modified permit before building. A simple deviation of a few centimetres can lead to months of proceedings.
• Photograph each stage of the building work. In the event of a dispute, this evidence is essential. A client in Petit-Quevilly was able to prove that his neighbour had exceeded the authorised height using dated photos.
• Consult a specialist solicitor as soon as you receive a formal notice. Do not try to regularise alone. A poorly handled prefectural order can worsen your situation. Maître Zakine helps you choose the best strategy.
• If you are a victim, act without delay. The limitation period for criminal proceedings is 6 years from completion of the works (Article 8 of the Code of Criminal Procedure). For a civil action for demolition, you have 30 years. But the longer you wait, the more reluctant the judge will be to order an expensive demolition.

Further analysis: related case law and developments

The Court of Cassation has reaffirmed this principle on several occasions. For example, in a judgment of 3 May 1995 (No. 93-85.543), it held that the subsequent regularisation of a planning infringement does not make the infringement itself disappear. More recently, the criminal chamber on 12 January 2021 (No. 20-81.234) specified that even if the prefect issues a modified building permit after completion of the works, criminal proceedings remain possible for the earlier period.

The trend of the courts is therefore to maintain a clear distinction between the time of the infringement and its regularisation. This means that builders cannot rely on an 'automatic regularisation'. Conversely, civil judges are increasingly inclined to refuse demolition if the regularised construction no longer causes an abnormal neighbourhood disturbance. The balance is subtle.

For the future, the legislature could clarify the effects of regularisation, but for now, the 1964 case law remains the reference.

Checklist before acting

• Do I have a valid building permit? Check the compliance of your project with the permit. If not, apply for a modified permit before starting any work.
• A neighbour accuses me of an infringement: what to do? Do not try to regularise alone. Immediately consult a solicitor to assess the risks and options.
• My neighbour has built illegally: can I act? Yes, even if he obtains a permit afterwards. Gather evidence (photos, witness statements) and bring the matter before the criminal court within 6 years of completion.
• What is the financial risk? The fine can be up to €120,000, plus damages and demolition costs. Regularisation can reduce the cost, but not cancel it.
• Can I negotiate a settlement with the town hall? Sometimes, but this does not erase the criminal infringement. Only a solicitor can advise you on the best approach.

Are you in a similar situation? A 30-minute initial consultation with Maître Zakine (€45) can save you months of proceedings — and often much more. Book an appointment →