TF, 02.09.2026, 1C_452/2026
Facts
The Milan Public Prosecutor's Office (Italy) is conducting criminal proceedings for aggravated fraud and money laundering against B. and C.
They are accused of deceiving an heir regarding the true value of her father's estate, leading her to sign a disadvantageous settlement and causing damages of at least 10 million euros.
The proceeds of the crime were allegedly reinvested through various shell companies, including some in Switzerland (Fact A).
In this context, the Italian authorities requested that Switzerland search the premises of A.________ SA, which had recently taken over the role of trustee for certain trusts previously managed by an entity linked to the defendants.
The Public Prosecutor's Office of the Canton of Ticino (MP-TI), acting as the executing authority, carried out the search and seized documents (Fact A).
In a closing decision dated April 28, 2026, the MP-TI ordered the transmission of all seized documentation to the Italian authorities.
Following an appeal by A.________ SA, the Appeals Chamber of the Federal Criminal Court (FCC) upheld this decision in a judgment dated August 11, 2026.
The FCC notably ruled that the handover of all documents was justified by the criterion of potential relevance and that attorney-client privilege or banking secrecy did not pose an obstacle (Fact B).
A.________ SA (hereinafter: the appellant) has filed a public law appeal with the Federal Supreme Court against the FCC's judgment.
It requests that the transmission of certain documents deemed irrelevant or covered by professional secrecy be excluded (Fact C).
Legal Grounds
In matters of international mutual legal assistance in criminal cases, an appeal to the Federal Supreme Court is only admissible if it concerns the disclosure of information protected by secrecy and involves a particularly important case (art. 84 para. 1 LTF) (recital 1.2).
A case is considered particularly important, in particular, when there is reason to believe that fundamental procedural principles have been violated or that the proceedings abroad suffer from serious deficiencies (Art. 84 para. 2 LTF).
This condition is interpreted restrictively, and it is the responsibility of the appellant to demonstrate how it is met (Art. 42 para. 2 LTF) (recital 1.2, 1.3).
The principle of proportionality, in conjunction with that of potential relevance, does not preclude the broad transmission of documents, especially in money laundering cases where it is necessary to reconstruct complex financial flows.
Mutual assistance may be extended if it reasonably aligns with the objective of the request and helps avoid the need for supplementary requests (recital 2.3).
Attorney-client privilege only protects activities typical of legal advice and representation in court.
Asset or trust management, even when performed by an attorney, is not covered (recital 2.2, 2.4).
The professional secrecy of financial institutions (Art. 69 FinIA), analogous to banking secrecy (Art. 47 Banking Act), does not, in principle, constitute an obstacle to mutual legal assistance in criminal matters (recital 2.4).
Application to the specific case
The appellant must demonstrate that their case is "particularly important" within the meaning of Art. 84 LTF for their appeal to be admissible (recital 1.3).
They invoke a violation of the principle of proportionality, arguing that the handover of documents concerning third parties or other trusts would be an arbitrary and overly extensive application of the potential relevance criterion.
The Federal Supreme Court rules that this argument is insufficient to establish a particularly important case.
The Federal Criminal Court correctly applied established case law in this matter, justifying the broad transmission by the need to reconstruct complex financial flows in a money laundering case.
Simply challenging the Federal Administrative Court's assessment of relevance does not constitute a particularly important case (recitals 2.1, 2.3).
The appellant also alleges a violation of attorney-client privilege.
She merely asserts that the documents concern "litigation," without providing further details or substantively challenging the Federal Administrative Court's conclusion that this was simply unprotected trust management activity.
This argument is insufficient to demonstrate the existence of a particularly important case (recital 2.4).
Likewise, the invocation of financial institution secrecy (Art. 69 FinIA) is futile, as the appellant fails to address the Federal Administrative Court's reasoning, which is consistent with case law, that such secrecy does not preclude mutual assistance (recital 2.4).
In the absence of a demonstration of a particularly important case, the appeal is inadmissible (recital 3).
Outcome
The Federal Supreme Court declares the appeal inadmissible (Ruling 1).
The court costs, set at CHF 2,000, are to be borne by the appellant (Ruling 2).