Jurisdiction of the coercive measures court to approve incidental findings from mutual legal assistance surveillance of a foreign communications platform

Facts

The Public Prosecutor’s Office of the Canton of Aargau conducted a criminal investigation against the accused on suspicion of aggravated violations of the Narcotics Act and money laundering. On 27 August 2021, it requested the Federal Office of Justice (FOJ) to apply to the competent US authority, in the context of mutual legal assistance, for the transmission of evidence, namely the message content (text and audio) of an ANOM cryptodevice used for the period from October 2019 until the closure of the ANOM platform, including all associated metadata (e.g. GPS data).

On 9 November 2021, the US Department of Justice transmitted the requested files to the FOJ on a USB stick. On 8 December 2021, the Aargau Cantonal Police prepared a report on this.

On 16 December 2021, the Public Prosecutor’s Office filed an application with the Coercive Measures Court (CMC) of the Canton of Aargau for approval of an incidental finding from the mutual legal assistance surveillance of the ANOM communications platform. On 20 December 2021, it supplemented its application. On 24 January 2022, the CMC ruled that the results of the foreign surveillance of the ANOM communications platform (content and metadata) could also be used in the criminal proceedings of the Swiss prosecution authorities against the accused.

After the approval application and the CMC’s ruling were notified to the accused, he filed an appeal with the Cantonal High Court of Aargau on 20 June 2022. He requested that the use of the incidental finding be denied and that the files transmitted in the context of mutual legal assistance be immediately destroyed. On 24 October 2022, the High Court declared the CMC’s ruling void and dismissed the appeal as moot.

Both the Attorney General’s Office of the Canton of Aargau (appeal filed on 25 November 2022) and the accused (appeal filed on 30 November 2022) appealed this decision to the Federal Supreme Court. Both appeals were dismissed.

Considerations

The Federal Supreme Court examined whether an incidental finding that was to be approved and used under Art. 274 in conjunction with Art. 278 CrimPC existed and whether the lower court’s finding that the CMC’s ruling of 24 January 2022 was void violated federal law.

International criminal law principle of territoriality and mutual legal assistance requirement: In international criminal law, the principle of territoriality applies, under which states may not carry out sovereign acts on foreign territory. The use of recordings obtained by foreign authorities in the context of international mutual legal assistance is not governed by the Swiss CrimPC, but by the law of the requesting state. In the present case, the recordings were obtained by US authorities and transmitted to Switzerland via the mutual legal assistance procedure. The conduct and admissibility of the surveillance were therefore governed by US law, not the Swiss CrimPC (Art. 54 CrimPC, Art. 1 IMAC in conjunction with Art. 4(1), Art. 31(2) and (3) and Art. 38(2) and (3) RVUS).

No applicability of Art. 278 CrimPC to incidental findings from foreign surveillance: The provisions of Art. 269 et seq. CrimPC relate to wiretaps that Swiss prosecution authorities have ordered and carried out in Switzerland in the context of a domestic criminal proceeding. Art. 278 CrimPC governs the use of incidental findings discovered in Switzerland in the context of such surveillance. In the present case, however, the issue was the use of recordings from a communications surveillance conducted abroad in the context of a mutual legal assistance request. A distinction must be made between incidental findings from domestic surveillance and those from foreign mutual legal assistance requests. An analogous application of Art. 278 in conjunction with Art. 274 CrimPC to incidental findings from foreign surveillance is not justified, as there is no legislative gap that would justify such an extension of the CMC’s jurisdiction.

No incidental finding within the meaning of Art. 278 CrimPC: Art. 278 CrimPC is intended to ensure that incidental findings newly discovered in the context of wiretaps under Art. 269 et seq. CrimPC may only be used in criminal proceedings if…