Encroachment on the Neighbouring Land: When a Court Decision Must Be Interpreted

Imagine: you live in Grande-Synthe, a nice house with a garden. You learn that your neighbour has built a garden shed that extends 30 centimetres onto your land. You obtain a judgment ordering the removal of this encroachment. But when the bailiff comes to inspect, the measurements stated in the judgment are wrong: a misplaced comma, and the shed is not the one that encroaches. Must you start all over again? Fortunately, no.

The Court of Cassation answers this question in a decision of 1 December 1971 (No. 70-11.006). It holds that a judge may interpret a prior judgment to correct a manifest material error (a simple clerical mistake in the figures), by referring to the expert report already on file. This avoids reopening a case already decided.

In practice, if the judgment orders the removal of the encroachment but makes a mistake in the numbers, the court of appeal may correct it without violating the authority of res judicata (the principle that a final decision cannot be challenged). A safeguard for owners.

The Facts: An Everyday Story

Mr Dumas, owner in Téteghem, built a house. Problem: part of the construction encroaches onto the neighbouring land, belonging to Mr Lefebvre. The latter sues Dumas for removal of the encroachment. An expert is appointed, who precisely measures the encroachment: the south-east corner of the house extends several decimetres onto the neighbouring plot.

The court of appeal issues a first judgment on 17 November 1969, ordering the removal of the part of the house that encroaches. But in the operative part (the part that orders), the numbers expressing the measurement of the encroachment contain a material error (a copying mistake, a misplaced comma). The bailiff in charge of enforcing the decision cannot determine precisely what must be demolished.

Dumas then applies to the same court of appeal for an interpretation: he disputes the extent of the encroachment. The court, in a second judgment, interprets the first one based on the expert report, which had never been contested by the parties. It corrects the error. Dumas appeals to the Court of Cassation: he argues that this second judgment violates the authority of res judicata, because it modifies the initial decision.

The Court of Cassation dismisses his appeal. It holds that the court of appeal did not violate the authority of res judicata, since it merely corrected a manifest material error by referring to the expert report, the only document on which the first judgment could be based.

The Reasoning of the Court — Analysed

The Court of Cassation relies on a fundamental principle: the authority of res judicata (Article 1351 of the Civil Code, now Article 1355). Once a decision is final, it cannot be challenged. But this principle has limits: interpretation and correction of material error.

Here, the court of appeal did not modify the substance of the decision. It merely clarified what the first judgment intended to say. How do we know this? Because the first judgment expressly referred to the expert report to order the removal of the encroachment. The expert's conclusions had never been contested. Therefore, to correct the numerical error, the judge could refer to that report.

Dumas's appeal argued that the court of appeal had violated the authority of res judicata by modifying the numbers. But the Court of Cassation responds that when a decision is ambiguous or contains a manifest material error, the judge may interpret it without changing it. In other words, interpretation is not a revision.

What few people know is that this solution is consistent with settled case law: the correction of material errors (such as a typo) is possible at any time, even after the decision has become final. This avoids long and costly appeals.

What This Means for You — In Practice

If you are an owner and you obtain a judgment ordering the removal of an encroachment, but the measurements are wrong, do not panic. You can ask the judge to interpret his decision (by way of an application for interpretation) without reopening the case. However, the error must be manifest, i.e., obvious from the file.

For a tenant in Téteghem, if your neighbour encroaches on the garden you rent, you can take legal action, but it is the owner who must defend his rights. You must inform him promptly.

A buyer should verify the boundaries before purchasing. Imagine: you buy a house in Grande-Synthe, and the boundary survey reveals an encroachment of 50 cm. If the seller already has a judgment ordering removal, but the measurements are wrong, the judgment can be interpreted.

In my practice, I have come across cases where a simple misplaced comma in a judgment blocked enforcement for months. Thanks to this case law, a quick correction can be obtained, often within a few weeks, avoiding a costly new expert report (count €2,000 to €5,000).

Four Tips to Avoid This Type of Dispute

• Carry out an amicable boundary survey before any construction: in Téteghem, a surveyor can precisely demarcate the plots for around €1,500. It is cheaper than a lawsuit.
• Keep all expert reports: they are the key to interpreting an erroneous judgment. Without them, correction is impossible.
• Check the operative part of the judgment: as soon as you receive a judgment, carefully read the numbers and measurements. If an error jumps out, ask for an immediate correction.
• Do not contest an expert report if you accept it: if you do not contest it, it becomes the reference for interpreting the judgment.

Further Reading: Related Case Law and Developments

This 1971 decision is part of a consistent line of authority. For example, the Court of Cassation has held (Civ. 3e, 15 December 1993, No. 91-18.497) that the judge may correct a material error affecting the description of a property in an eviction order. Similarly, in matters of easement (right of way over another's land), a measurement error in a judgment can be corrected by interpretation (Civ. 3e, 8 July 2009, No. 08-16.977).

The trend is thus liberal: courts favour judicial efficiency by allowing errors to be corrected without reopening proceedings. However, the interpretation must not lead to modifying the judge's intention. If the error is substantial (e.g., the judgment orders the demolition of a part that was never intended), a new trial will be necessary.

Checklist Before Taking Action

1. Check the judgment: is the error material (figure, name, address) or does it go to the merits?
2. Gather the documents: expert report, parties' submissions, any document showing the judge's intention.
3. Consult a lawyer: the application for interpretation must be reasoned and filed with the court that rendered the decision.
4. Time limit: there is no deadline for requesting correction of a material error, but it is prudent to act quickly.
5. Cost: expect around €500 to €1,500 in lawyer's fees for a simple application, plus court fees (a few dozen euros).

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