TF, 08.01.2026, 1C_2/2026
Facts
As part of an investigation into so-called "CumEx" transactions, the Cologne Public Prosecutor's Office (Germany) is investigating C.________ for tax fraud and fraud, and his wife A.________, along with others, for money laundering. A.________ is also the chair of the board of directors of B.________ AG.
The German authorities submitted a request for mutual legal assistance to Switzerland, seeking the handover of banking documents related to accounts held by A.________ and B.________ AG. The Public Prosecutor's Office of the Canton of Grisons, acting as the executing authority, authorized the handover of these documents in a final decision. A previous appeal against a similar decision had already been rejected by the Federal Criminal Court, and the Federal Supreme Court subsequently declined to hear the case.
A.________ and B.________ AG appealed the new final decision of the Grisons Public Prosecutor's Office to the Federal Criminal Court, which rejected their appeal. They then filed an appeal with the Federal Supreme Court.
Legal Analysis
UnderArt. 84 of the Federal Supreme Court Act (FSCA), an appeal in matters of international mutual legal assistance is only admissible if it concerns, among other things, the transmission of information protected by secrecy and involves a "particularly important case."
A case is considered particularly important if, for instance, there are reasons to believe that fundamental procedural principles have been violated or that the foreign proceedings exhibit serious flaws (Art. 84 para. 2 FSCA). It is the appellant's responsibility to demonstrate why their case holds such importance (heightened duty to provide grounds).
In principle, Swiss mutual assistance authorities do not review the criminal proceedings of the requesting state, especially if it is a member of the European Convention on Human Rights (ECHR) with a comprehensive system of legal remedies. Mutual assistance can only be refused on grounds of public policy in cases of flagrant denial of justice. Furthermore, as a general rule, only natural persons located within the territory of the requesting state who are concretely exposed to a violation of their procedural rights may invoke such defects.
Application to the Case
The appellants argue that the case is particularly important because the criminal proceedings conducted in Germany against C.________ (A.________'s husband) flagrantly violate Articles 6 and 7 of the ECHR (right to a fair trial, presumption of innocence).
The Federal Supreme Court rejects this argument. Firstly, there is no objective evidence of a flagrant denial of justice in the German proceedings that would justify refusing mutual assistance.
Secondly, the alleged procedural violations concern C., not the appellants themselves. A. (the first appellant) resides in Switzerland and is therefore not directly exposed to the alleged defects in the German proceedings. B.________ AG (the second appellant) is a legal entity and does not even claim to be an accused party in the foreign criminal proceedings.
The grievances raised are therefore not of a nature to prevent the handover of the documents and, consequently, are insufficient to qualify the case as "particularly important" within the meaning of Art. 84 FSCA. The same applies to the grievance regarding the violation of the principle of due speed, which must be raised within the German proceedings.
Outcome
The Federal Supreme Court does not admit the appeal. The legal costs are charged to the appellants.
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