Supplementary police custody: nullity of interviews but not of the measure — implications for foreigners

Imagine: you own a flat in Bollène, and you rent it to a foreign national. One day, this tenant is placed in police custody for a minor offence. During this custody, the police question him about other facts — for example, handling stolen goods — without informing the prosecutor. Later, removal proceedings are initiated, and your tenant ends up in the detention centre in Pertuis. You wonder: is this supplementary police custody valid? Can the judge annul the entire procedure?

This is exactly the question put to the Court of Cassation in its judgment of 23 June 2021 (No. 19-22.678). A question that touches on the balance between the rights of the defence and the effectiveness of the investigation, and which has direct consequences for irregular foreigners — and indirectly for the landlords who house them.

The Court's answer is nuanced: the failure to inform the prosecutor vitiates the interviews on the new facts, but not the custody itself. And for foreigners, release from detention is not automatic. Analysis.

The facts: a story that happens every day

The case begins with an ordinary police custody. Mr X, a foreign national, is placed in custody for handling stolen goods — an offence consisting of possessing stolen property. But the police do not stop there: during custody, they also hear him about other facts, described as "supplementary handling", without informing the public prosecutor. This additional hearing is what is called "supplementary police custody": it extends the initial measure to investigate new suspicions.

However, Article 65 of the Code of Criminal Procedure requires the judicial police officer to inform the prosecutor "without delay" of the new facts and their legal classification. In this case, this information was not given. Result: the procedure is contested, and Mr X appears before the liberty and detention judge to seek annulment of the custody and, by extension, of the administrative detention that followed (he was in an irregular situation and subject to an obligation to leave French territory).

The judicial journey is complex: first, the first-instance judge annuls the custody and orders release from detention. But the Court of Appeal reverses this decision, holding that the irregularity did not infringe Mr X's rights. The Court of Cassation is then seised to decide. After several twists and turns, it delivers a landmark judgment on 23 June 2021.

The reasoning of the court — explained

The Court of Cassation first recalls the legal basis: Article 65 of the Code of Criminal Procedure, which requires informing the prosecutor of new facts. And Article 802 of the same code, which provides for the nullity of irregular acts. But it specifies: this nullity is not automatic for the entire custody.

In clear terms, the Court distinguishes between two things: on the one hand, the interviews on the new facts (those conducted without informing the prosecutor) and, on the other hand, the measure of custody itself. The interviews are void, because the failure to inform necessarily causes prejudice (i.e., it infringes the person's rights). Conversely, the initial custody remains valid, as do the acts that do not depend on the annulled interviews.

In other words, if you are in custody for theft, and you are questioned without the prosecutor being informed about handling stolen goods, your statements on the handling cannot be used. But the custody for theft remains lawful, and the evidence gathered before the additional interview is valid.

The Court goes further for foreigners in administrative detention. Article L. 552-13 of the Code on the Entry and Residence of Foreigners and the Right of Asylum (CESEDA) allows the judge to order release from detention in case of procedural irregularity, but only if this irregularity has "infringed the rights of the foreigner". The Court holds that the nullity of the interviews does not automatically constitute an infringement of rights justifying release. Concrete prejudice must be demonstrated — for example, that the duration of detention was extended because of the unlawful interview.

However, the lower court judges must examine the circumstances. In the case decided, the supplementary custody had not extended the total duration of the measure (it took place within the same timeframe as the initial custody). Consequently, no prejudice was established, and the detention was maintained.

What few people know is that this decision is part of a consistent line of case law. The Court of Cassation ensures that nullities are not automatic, but conditional on prejudice. A pragmatic approach that avoids cascading annulments for minor defects.

What this changes for you — practically

For landlords: if you rent to an irregular foreigner, know that their removal may be delayed if the custody procedure is tainted by irregularities. But this decision shows that nullity is not systematic. If you are faced with a tenant in detention, do not count on automatic nullity to get them released faster.

For foreign tenants: if you are placed in custody and the police question you about facts not notified to the prosecutor, your lawyers can request the annulment of those interviews. But the custody itself remains valid, and administrative detention may be maintained if the irregularity did not extend your detention.

For real estate professionals (agents, notaries): this decision has an indirect impact on rentals. A foreign tenant in detention may stop paying rent. If the detention is annulled, they can return to the premises. But if the detention is maintained, the landlord can initiate eviction proceedings. undefined, I have come across cases where the irregularity of custody was raised to challenge eviction. Now, concrete prejudice must be proved.

Concrete example in Pertuis: a tenant is placed in detention at the administrative detention centre (CRA) of Pertuis. He had been in custody for lack of a residence permit, and during this custody, he was questioned about handling stolen goods without the prosecutor being informed. His lawyer seeks nullity of the detention. The judge examines: did the additional interview extend the custody? If yes, prejudice is established and release is possible. If not, detention is maintained.

If you are in this situation, you must check the timeline: did the supplementary custody last longer than the initial custody? If yes, you have a chance of obtaining nullity of the detention. If not, you will need to invoke other irregularities.

Four tips to avoid this type of dispute

• Check the regularity of the procedure from the outset: if you are a lawyer or assisting someone in custody, immediately request a copy of the record of information to the prosecutor. The absence of this information is a ground for nullity of additional interviews.
• Document the duration of custody: note the start and end times of the measure, as well as the times of interviews. This will help demonstrate whether the supplementary custody extended the initial measure.
• For foreigners in detention: do not focus solely on custody. Other irregularities may exist (lack of interpreter, absence of lawyer, etc.). A holistic approach is more effective.
• For landlords: if your tenant is placed in detention, consult a lawyer specialised in immigration law. An annulment of detention may allow the tenant's return, but also remedies for unpaid rent.

Further reading: related case law and developments

This decision confirms a principle established by the Court of Cassation in several earlier judgments. For example, in a judgment of 10 February 2021 (No. 20-84.123), the Court had already held that the failure to inform the prosecutor during custody only rendered void the acts subsequent to the irregularity, and not the entire procedure. The 2021 decision extends this reasoning to administrative detention.

Another important decision is that of 18 November 2020 (No. 20-81.456), where the Court specified that the nullity of interviews does not extend to acts that are not their necessary and exclusive support. For example, a search carried out before the unlawful interview remains valid.

The trend of the courts is therefore towards strict control of the regularity of custody, but with a concrete assessment of prejudice. In the future, judges are likely to require a precise demonstration of the link between the irregularity and the infringement of rights. A development that places responsibility on lawyers to provide tangible evidence.

Checklist before acting

• Question: Is supplementary custody always void?
  Answer: No, only the interviews on the new facts are void if the prosecutor was not informed. The custody itself remains valid.
• Question: Can I request release from detention if custody is irregular?
  Answer: Yes, but only if you prove that the irregularity infringed your rights (e.g., extension of detention).
• Question: What are the time limits for challenging?
  Answer: The challenge to custody must be raised at the hearing before the liberty and detention judge. After this time, it is more difficult to obtain nullity.
• Question: What is the cost of a consultation?
  Answer: An initial consultation with a specialised lawyer costs between €45 and €150. But it can avoid prolonged detention and higher legal fees.

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 →