Use of Chance Finds from IMSI Catcher Operations

Facts

The Public Prosecutor's Office of Lenzburg-Aarau conducted a criminal investigation against [A.] for qualified drug offenses. Between March and December 2016, the Compulsory Measures Court of the Canton of Aargau approved various secret surveillance measures against the accused as well as the use of chance finds. [A.] challenged these measures with the cantonal appeal authority. The High Court of the Canton of Aargau dismissed the appeal.

Considerations

The Federal Supreme Court decided that the use of the chance finds against [A.] was in compliance with federal law. The IMSI catcher operations that led to the chance finds had been approved by the competent courts. There was already a sufficient legal basis for the use of the IMSI catcher to determine call and device numbers under the old legal situation (prior to March 1, 2018).

The Federal Supreme Court examined whether the legal requirements for the use of the chance finds…