Evidence and fairness: what you can produce in a French separation, and what can backfire

When you separate, it is natural to want to show the judge everything. But not all documents carry the same weight, and some ways of obtaining them can expose you to criminal charges. This guide covers what you can usually produce without difficulty, what raises problems, and good habits to adopt. It is about French law only.

The principle: evidence is free, but it must be fair

In French civil matters, evidence is in principle free. You can present writings, messages, invoices, and witness statements. The judge then decides how much weight to give them.

That freedom has a limit: evidence must be obtained fairly. French lawyers call this loyauté de la preuve (fairness in obtaining evidence). A document obtained by deceiving the other person, or by violating their privacy, can be set aside. It can also be held against you.

For divorce, the French Civil Code (Code civil) sets two specific rules:

• Article 259: the facts relied on may be established by any means of evidence, including an admission. But descendants can never be heard on the grievances the spouses raise against each other.
• Article 259-1: a spouse may not produce evidence obtained through violence or fraud.

The rule on descendants deserves emphasis. Your children should never serve as witnesses or messengers in a conflict between adults. Do not ask them for a statement, an account, or a message to pass on.

What you can generally produce

These items rarely raise a problem in principle, because you obtained them normally. The judge then weighs their value.

• Messages you received yourself: texts, messages in a messaging app, emails that arrived in your own mailbox, voicemails left for you.
• Your own dated notes: a log kept day by day, with the date, place, what happened, and who was there.
• Documents in your own name: statements for your own account, pay slips, letters you received, contracts.
• Proof of expenses: receipts, invoices, transfer confirmations.
• Witness statements that meet article 202 of the French Code of Civil Procedure (Code de procédure civile, CPC): written by the witness personally, dated, signed, with a copy of their ID and a statement that they know it will be used in court.
• *Findings by a commissaire de justice*** (a French court officer), made within the law.

Keep the context

A screenshot on its own can be contested. A sentence cut out of a conversation can change meaning. A few simple habits:

1. Keep the whole conversation, not just the part that matters to you.
2. Make sure the date, time, and sender are visible.
3. Never alter a screenshot: no misleading crop, no highlighting that hides text.
4. Keep the original on your phone or in your mailbox, in addition to the screenshot.

In Prismo, a screenshot shared from another app is filed with its full source, so the context is not lost.

What can backfire

Some methods seem convenient. They can nonetheless be criminal offenses under French law, and lead the other party to file a complaint against you.

• Recording someone’s private words without their consent, or capturing their image in a private place: covered by article 226-1 of the French Criminal Code (Code pénal).
• Geolocating a person without their consent, for example with a hidden tracker or an app installed without their knowledge: article 226-1 also covers this.
• Opening, diverting, or reading someone else’s correspondence, including their emails: the subject of article 226-15 of the Criminal Code.
• Fraudulently accessing a computer system: going through the other person’s phone, or logging into their online account or mailbox with a guessed or old password. Covered by article 323-1 of the Criminal Code.

Having been a couple, or knowing the passcode, does not make these actions lawful.

The 2023 ruling: a door left ajar, not a permission

On December 22, 2023, the full bench (Assemblée plénière) of the Cour de cassation, France’s highest court for civil and criminal matters, changed the rule. In civil matters, evidence obtained unfairly or unlawfully is no longer automatically excluded.

The judge must now weigh the right to evidence against the other rights at stake, such as respect for private life. The evidence can be admitted only if producing it is indispensable to exercising the right to evidence, and if the infringement of the other person’s rights is strictly proportionate to the aim pursued.

It is important to understand what this means:

• It does not make such evidence acceptable in principle. The judge can still set it aside.
• It does not remove criminal liability. A secret recording can still lead to prosecution, even if a civil judge examines it one day.
• Whether evidence is “indispensable” is assessed case by case. If other documents can establish the same facts, the contested item is unlikely to help.
• In a divorce, how this case law fits with article 259-1 of the Civil Code is a question for your lawyer.

In practice, it is best not to rely on this change to justify a questionable method.

Good habits before producing a document

1. Talk to your lawyer before handing over a sensitive item: a recording, a photo taken in the other person’s home, a message you were not the recipient of. Your lawyer can tell you whether it is useful, and whether it carries a risk.
2. Favor what you experience and receive directly: your dated notes, messages addressed to you, your own receipts.
3. Write down facts as they happen, plainly: date, time, place, what was said or done, who was present. A precise, regular account is often more telling than a dramatic document.
4. Ask direct witnesses for statements (neighbors, friends, relatives), and never your children.
5. Do not try to provoke the other person to get a reaction on record.

Prismo made a clear choice: the app offers no surveillance feature. No tracking of the other parent, no interception, no access to their accounts. It helps you organize what already belongs to you. You can learn more about our approach to security.

If you are in danger

If your safety or your children’s safety is threatened, building a file is not the priority. In France, call 17 or 112 in an emergency. 3919 listens to and guides women facing violence. 119 is the national helpline for children at risk.

Key takeaways

• In French civil matters, evidence is free, but it must be obtained fairly.
• Messages you received, your dated notes, your receipts, and witness statements that meet article 202 of the CPC are generally usable.
• Secretly recording, geolocating, reading emails, or going through the other person’s phone can be a criminal offense, whatever happens in the civil case.
• Since 2023, a judge may examine unfairly obtained evidence under strict conditions, but that is neither a guarantee nor protection from criminal liability.
• Children are never witnesses to grievances between parents. Discuss every sensitive item with your lawyer before producing it.