Expert Determination: What Judges Cannot Do Without You

You are a property owner in Hyères and have just received the expert's report in your boundary dispute. Unsatisfied, you contact the expert directly to ask for additional information. Fatal mistake. This simple step can destroy your entire case.

Why? Because the law is clear: only the judge can ask the expert to clarify their findings. Any document resulting from a unilateral request is inadmissible. This is what the Court of Cassation recalled in a judgment of 25 May 1992, a decision that still holds authority today.

In this article, I explain how this rule applies in practice, through a case that pitted a buyer against a car dealer in Strasbourg. You will see that the same principles govern property expert determinations in Toulon and elsewhere.

The Facts: A Story That Happens Every Day

In 1981, Mr and Mrs X buy a new car from the company Garage Hess, now known as Centrale Automobile de Strasbourg (CAS). Very quickly, defects appear. The couple sue the seller. The Instance Court of Strasbourg orders an expert determination (technical examination entrusted to a specialist appointed by the judge).

The expert files their report. But CAS, dissatisfied with the findings, contacts the expert directly and obtains a supplementary statement (a written document in which the expert gives their opinion outside the judicial framework). Armed with this document, CAS obtains from the court a payment order (a quick decision ordering payment of a sum) against Mr and Mrs X. The latter object, and the case goes up to the Colmar Court of Appeal.

The Court of Appeal relies, at least in part, on this irregular statement to find against Mr and Mrs X. The latter appeal to the Court of Cassation. The Court of Cassation sets aside the judgment, holding that the Court of Appeal violated Article 245 of the new Code of Civil Procedure (old Code, the principle of which is restated in current Article 245).

The Reasoning of the Court — Analysed

The Court of Cassation relies on Article 245, paragraph 1, of the new Code of Civil Procedure (now Article 245 of the Code of Civil Procedure). This provision states that "the judge may invite the expert, the parties and third parties to provide explanations or information". It follows that only the judge, and not a party, may ask the expert to supplement, clarify or explain their findings.

In this case, the Colmar Court of Appeal had used a statement that the expert had given at the request of CAS, without any referral by the judge. However, this statement had not been submitted to adversarial debate (exchange between the parties) within the proceedings. The Court of Cassation considers that even if the Court of Appeal relied only partially on this document, the decision is tainted by irregularity. It recalls that the principle of adversarial proceedings (right of each party to discuss evidence) is fundamental.

This decision is a mere confirmation of the rule, but it is important because it severely penalises any deviation. It shows that judges cannot rely on evidence obtained in violation of procedural rules, even if that evidence seems relevant.

What This Changes for You — In Practice

For landlord owners (people who let a property): if you are in dispute with your tenant and an expert determination is ordered, never contact the expert directly. Any request must go through the judge. A statement obtained outside this framework will be excluded from the proceedings, which can weaken your case.

For tenants: if your landlord has had a private expert report prepared (expertise amiable, out of court), you can challenge its validity. But note, a private expert report is not subject to the same rules. The decision only concerns court-ordered expert determinations.

For purchasers (people who buy a property): imagine you buy a flat in Toulon and hidden defects (non-apparent defects) appear. A court-ordered expert determination is ordered. If the seller obtains a supplement from the expert in secret, this document can be challenged. You will save time and money.

Quantified example: in Hyères, a property owner had to pay €3,000 for an expert determination in a boundary dispute. The expert provided a supplementary statement at the neighbour's request. The judge excluded this statement, and the owner had to start the procedure again, losing 6 months and an additional €1,500.

Four Tips to Avoid This Type of Dispute

• Never contact the expert directly. All communication must go through the judge. If you have a question, address it to the court.
• Check the expert report as soon as you receive it. You have 15 days to ask the judge for clarification, not the expert.
• Keep all evidence of your steps. Keep a written record of every exchange with the court and the expert.
• Use a specialist lawyer. A professional knows the procedural rules and will avoid pitfalls.

Further Analysis: Related Case Law and Developments

The rule established in 1992 has been confirmed subsequently. For example, in a judgment of 11 June 2014 (No. 13-18.066), the Court of Cassation recalled that a judge cannot rely on a private expert report that has not been subject to adversarial debate. The trend is therefore towards increased protection of the adversarial principle.

Since the reform of civil procedure in 2019, Article 245 of the Code of Civil Procedure has been amended to strengthen the judge's role in directing the expert determination. The parties have more rights to participate in the operations, but the prohibition on directly soliciting the expert remains unchanged.

For the future, we can expect courts to become increasingly strict on compliance with these rules, especially in property disputes where financial stakes are high.

In Practice: What to Do

FAQ

• What if the expert spontaneously sends me a supplementary opinion? Do not accept it. Immediately inform the judge and the other party. The opinion cannot be used.
• Can I request a counter-expert determination? Yes, but only from the judge. You must give reasons for your request (expert error, omission, etc.).
• What are the time limits for challenging an expert report? You have until the closure of the proceedings. In practice, act within 15 days of receiving the report.
• How much does a court-ordered expert determination cost? Between €1,000 and €10,000 depending on complexity. The costs are advanced by the party requesting the expert determination.
• Can I use a private expert report before the judge? Yes, but it does not have the same force as a court-ordered expert determination. The judge may disregard it if it is not adversarial.

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