Lawyer's professional secrecy: when an 'official' letter is excluded from proceedings

Imagine: you are the owner of a commercial premises in Six-Fours-les-Plages, and your tenant is accumulating rent arrears. You eventually send him a formal notice to pay, then a court summons. But then your lawyer receives a letter from the opposing lawyer, bearing the mention 'official', in which he claims that you are 'seeking by any means to create payment incidents'. Furious, you want to use this letter to prove the tenant's bad faith. But the judge tells you: this letter is covered by professional secrecy, it cannot be used. Surprising, isn't it?

Yet this is exactly what the French Supreme Court decided in this judgment of 12 October 2016 (No. 15-14.896). A decision that forcefully reminds that a lawyer's professional secrecy is general and absolute, and that the mention 'official' is not a mere formality: it has a very precise meaning, and if it is used improperly, the letter remains confidential. So, what can you really do with lawyers' letters? And what are the risks of trying to use them?

This article explains everything to you, step by step, with concrete examples, so that you know exactly where you stand. Because this kind of detail can tip the scales in a trial.

The facts: a story that happens every day

The case began in 2005, in Bourges. The company Du Prado (the landlord) granted a commercial lease to a tenant. But very quickly, the rents were no longer paid. The landlord then served a formal notice to pay, followed by a summons for termination of the lease. Problem: these documents were not served at the tenant's registered office, but at the leased premises, where the company was still located. A procedural error? Perhaps. But the real twist came elsewhere.

In the course of this procedure, the landlord received several letters from the tenant's lawyer, all bearing the mention 'official'. In these letters, the tenant's lawyer claimed that the landlord was 'seeking by any means to create payment incidents'. The landlord saw this as proof of the tenant's bad faith and produced these letters before the judge in summary proceedings. But the tenant objected: these letters are confidential, they cannot be used!

The court of Bourges, in an interim order of 12 March 2015, upheld the tenant's objection: the letters were excluded from the proceedings because they did not meet the conditions to benefit from the 'official' mention. The landlord, dissatisfied, appealed to the Supreme Court. But the Supreme Court confirmed: a lawyer cannot disclose any information covered by professional secrecy, except in very strict exceptions. And these letters, which contained subjective assessments, were not mere procedural documents. They therefore remained secret.

The reasoning of the court — dissected

The Supreme Court relied on two fundamental texts. First, Article 66-5 of the Law of 31 December 1971, which lays down the principle: 'In all matters, whether in the field of advice or in that of defence, consultations addressed by a lawyer to his client or intended for that client, correspondence exchanged between the client and his lawyer, between the lawyer and his colleagues, with the exception for the latter of those bearing the mention "official", interview notes and, more generally, all documents in the file are covered by professional secrecy.' Next, Article 3.2 of the national internal regulations of the legal profession, which defines what an 'official' letter is: it must be 'equivalent to a procedural document' and must not refer to any prior confidential writing, statement or element.

The judges analysed the disputed letters: they contained value judgments ('seeking by any means to create payment incidents'). This is not a mere procedural document, such as a summons or a notification. It is an opinion, a defence strategy. However, professional secrecy protects everything relating to defence and advice. The 'official' mention cannot be used to circumvent this secrecy. If it is affixed to a letter that is not a genuine procedural document, it is ineffective: the letter remains confidential.

The Supreme Court therefore dismissed the landlord's appeal. It confirmed that a lawyer's professional secrecy is 'general and absolute', except for limited exceptions (defence of the lawyer himself, disclosure authorised by law). In short, you cannot use an opposing lawyer's letter simply because it bears the mention 'official': it must actually be a procedural document. And if it contains assessments, it is excluded from the proceedings.

What this changes for you — concretely

For landlord-owners: if you receive a letter from your tenant's lawyer with the mention 'official', do not celebrate too quickly. Before producing it in court, ask your lawyer to check whether it is really a procedural document (a summons, a service of judgment, etc.) or whether it contains comments. If it is the latter, you risk having it rejected, as in this case. Concrete example: in La Garde, a landlord who produces such a letter to prove his tenant's bad faith could see his argument dismissed and lose the case — with legal costs of €3,000 to €5,000.

For tenants: this is a protection. The opposing lawyer will not be able to use your confidential exchanges with your lawyer, unless they are genuinely procedural documents. You can therefore freely discuss your strategy with your counsel, without fear that it will be used against you. However, be careful: if you yourself disclose these exchanges, you risk violating professional secrecy.

For real estate professionals (agents, notaries): when you receive letters from lawyers, do not forward them to your client without consulting a lawyer. You could inadvertently violate professional secrecy. And if you are invited to a meeting with lawyers, know that everything said there is confidential.

If you are in this situation, you should immediately seek advice from a lawyer before using a letter received from the opposing lawyer. A quick consultation can save you from making an irreparable mistake.

Four tips to avoid this type of dispute

• Never produce a letter from an opposing lawyer without your own lawyer's advice. Even if it bears the mention 'official', it may be confidential. Your lawyer will check whether it falls within the exceptions.
• If you receive a letter from a lawyer, do not disclose it to third parties. You could be sued for breach of professional secrecy. Keep it for your lawyer only.
• In case of a dispute, prefer exchanges by bailiff's acts rather than 'official' lawyer letters. A formal notice to pay or a court summons are procedural documents, clearly not confidential.
• Have your 'official' letters drafted by an experienced lawyer. He will know how to comply with the strict conditions: no reference to confidential elements, no subjective assessment, and purely procedural content.

Further reading: related case law and developments

This decision is part of a consistent line of the Supreme Court. Already, in a judgment of 29 June 2010 (No. 09-15.221), the Court held that professional secrecy covers all correspondence between lawyers, except those bearing the mention 'official' and meeting strict criteria. More recently, a judgment of 15 March 2023 (No. 21-25.002) reminded that even exchanges between a lawyer and his client in the context of mediation are protected. The trend is therefore towards strengthening professional secrecy, considered a pillar of the rule of law.

What does this trend mean for the future? Lawyers will become increasingly cautious before using opposing correspondence. And litigants will have to learn to distinguish procedural documents from mere correspondence. At a time when digital evidence (emails, SMS) is multiplying, this issue becomes crucial. The Supreme Court seems determined to protect the confidentiality of exchanges between lawyer and client at all costs.

Checklist before acting

Before using a letter from an opposing lawyer, ask yourself these questions:

• Does the letter bear the mention 'official'? If so, is it really a procedural document (summons, service, etc.) or does it contain comments?
• Have you sought your lawyer's advice on using this letter in court?
• If you are a tenant, have you shared this letter with a third party (friend, family, advisor)? This could breach professional secrecy.
• If you are a lawyer, does your 'official' letter comply with the conditions of the national internal regulations?

FAQ:

• Can I use a letter from an opposing lawyer that accuses me of bad faith, even if it bears the mention 'official'? No, if this letter contains subjective assessments, it remains confidential and cannot be produced in court.
• What should I do if my lawyer receives an 'official' letter from the opposing lawyer? Your lawyer must verify whether it meets the conditions. If not, he must treat it as confidential and not disclose it without the sender's consent.
• What are the time limits for challenging the production of 'official' letters in court? This must be done as soon as the document is communicated, before the hearing. After that time, the judge may refuse to exclude them.
• How much does a lawyer consultation on this subject cost? Expect between €150 and €300 for a one-hour consultation, depending on complexity.

Are you 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 →