Sealing Procedure – General Principles and the Case of the Smartphone

A summary prepared by Alexandre Reymond, attorney-at-law

The seizure and search of documents, a computer or a telephone are common in criminal proceedings. Since a mobile phone is an immense source of information, the criminal authorities (generally the public prosecutor) often decide to seize it and search it. The result of this search will be included in the investigation file and will be accessible to all parties, such as all defendants and complainants; it may also be placed on record in other files relating to other investigations. However, the defendant, or any entitled person, may preserve certain secrets through the sealing procedure, subject to certain conditions. The case law of the Federal Supreme Court provides guidance on the procedural obligations of the person requesting sealing and the scope of the grounds that may be invoked.

I. The sealing procedure

The purpose of sealing is to remove documents from the public prosecutor’s reach when there is a reason to keep them confidential. The person whose documents or objects have been seized by the investigators has a period of three days to request sealing. The criminal authority then has a period of twenty days to refer the matter to the judge (generally the Compulsory Measures Court) and request the lifting of the seals. The judge rules quickly and gives the person who requested the seals a single period of ten days to state their position on the lifting of the seals. The judge may be assisted by an expert to examine the documents, recordings or objects under seal.

The person requesting the sealing of documents or objects must make it plausible that they have grounds to seek the sequestration. The criminal authority must affix the seals immediately. It is not allowed to make a copy of the documents, to unlock the telephone or to make a mirror copy. If a copy or unlocking is necessary, it is the court that must do so, possibly by appointing a specialized entity. The Federal Supreme Court has excluded that this task be carried out by the investigating authority (ATF 148 IV 221).

Holders of seized objects and documents who oppose their search must set out the grounds invoked in a substantiated manner at the latest during the judicial procedure for lifting the seals, provided that a request for sealing that complies with form and time limits has been filed and that a request to lift the seals has been lodged.

In principle, the public prosecutor may not reject the request for sealing; it must affix the seals and, where applicable, request their lifting from the competent judge. The Federal Supreme Court nevertheless accepts that the public prosecutor may reject the sealing request where it is manifestly abusive, ill-founded or late (TF, arrêt 7B_313/2024 du 24 septembre 2024).

The risk that the public prosecutor may reject the sealing request requires the applicant to explain immediately the reason for the request and to demonstrate that it is not late. If necessary, they may complete their request when the judge gives them the opportunity to state their position on the lifting of the seals (art. 248a al. 3 CPP).

Applicants requesting sealing must assist the Compulsory Measures Court in reviewing and sorting the documents. They must demonstrate the existence of a secret and the overriding interest in maintaining that secret by identifying the documents concerned. This is all the more true because the judge responsible for lifting the seals does not know the details of the investigation and the public prosecutor cannot yet examine the sealed files. The persons concerned must also identify the items which, in their view, are subject to secrecy or which are manifestly unrelated to the criminal investigation so as to allow the court to separate the documents covered by secrecy from the other documents. This applies in particular where they have requested the sealing of very voluminous or complex documents or files (ATF 138 IV 225).

With regard to a smartphone or a computer, it is necessary to indicate to the judge where and how the documents covered by secrecy or relating to the private sphere are stored. In order to reach a decision, the judge examines all the documents and recordings subject to sealing. However, the judge may rely on an expert. This is particularly indicated to assist the judge in sorting the contents of a telephone.

The decision of the Compulsory Measures Court is final (art. 248a al. 4 CPP). A further appeal may, however, be lodged with the Federal Supreme Court provided the appellant demonstrates the existence of irreparable harm.

II. Grounds for ordering sealing

Since the amendment to the Code of Criminal Procedure that entered into force in 2024, the grounds that may be invoked to request sealing are exhaustively listed by law. Sealing may be requested for:

• documents concerning contacts between the defendant and their defence counsel;
• the defendant’s personal documents and correspondence, where the interest in the protection of personality outweighs the interest in criminal prosecution;
• objects and documents concerning contacts between another person and their lawyer;
• objects and documents concerning contacts between the defendant and a person who has the right to refuse to testify under arts. 170 to 173 CPP; these persons are essentially those subject to official secrecy and professional secrecy or who are covered by the protection of sources for media professionals.

Professional secrecy applies in particular to clergy, lawyers, defence counsel, notaries, patent advisors, physicians, dentists, chiropractors, pharmacists, psychologists, nurses, physiotherapists, occupational therapists, midwives, dieticians, optometrists, osteopaths, as well as their auxiliaries.

It is important to note that other secrets, such as trade secrets and banking secrecy, do not allow the request for sealing (TF, 7B_950/2024 du 15 novembre 2024). Where a ground for sealing is plausibly invoked, the legality of the search may also be challenged, but only on an ancillary basis (TF, 7B_950/2024 du 15 novembre 2024).

It is common for the public prosecutor to seize a telephone and order it to be searched. In such a case, the entitled person may invoke the aforementioned grounds, for example where the mobile phone contains medical documents or correspondence with their lawyer. As regards the telephone, they will generally be able to invoke confidentiality over their personal documents and correspondence. This ground concerns the protection of the private sphere, guaranteed by the Constitution and the European Convention on Human Rights.

The Federal Supreme Court accepts that it is a matter of common knowledge that smartphones used privately generally contain a multitude of sensitive data relating to the intimate sphere of their owner and that it can therefore be assumed without further ado that a (complete) search of privately used smartphones infringes personal notes and correspondence (TF, 7B_145/2025 du 25 mars 2025).

However, unlike the other grounds permitting sealing, the protection of the private sphere is not absolute and depends on a balancing of interests between the interest in the protection of personality and the interest in criminal prosecution. The party requesting sealing must therefore demonstrate that their interest in the protection of their personality could outweigh the interest in criminal prosecution. In any event, the Federal Supreme Court considers that a general reference to private correspondence or photos is not sufficient (TF, 7B_145/2025 du 25 mars 2025).

The duty to cooperate in sorting does not mean that the defendant is obliged to provide their access codes and passwords.

III. Conclusions

Anyone faced with the seizure and search of their telephone is not without means to protect fundamental rights and certain secrets. In addition to the fact that all coercive measures must comply with fundamental principles such as proportionality and the existence of sufficient suspicions (art. 197 CPP), the holder may invoke the existence of a secret protected by law as well as respect for private life.

Anyone requesting the sealing of documents or a smartphone must ensure that the request is filed within three days. If compliance with this time limit is likely to be disputed, they should also explain why the request is not late.

Next, the person making the request must also indicate which ground(s) are invoked. On that occasion, they must also specify which documents those grounds apply to. When invoking respect for the private sphere, they must indicate why the protection of their private interest in secrecy should prevail over the interest in criminal prosecution.

Finally, if the public prosecutor requests the lifting of the seals, the holder must cooperate in the sorting of documents to be carried out by the judge.

Needless to say, the assistance of a lawyer in this technical procedure is recommended and increases the chances of removing from the criminal authority those documents protected by professional secrecy or relating to the private or intimate sphere.

Unofficial English translation – for information purposes only.