Federal Supreme Court, 03.10.2026, 6B_460/2025
Facts
On August 9, 2022, police officers attempted to stop A.________, who was urinating in public. He fled, jumped into a river, and emptied the contents of three bags of cocaine he was carrying into the water. On December 6, 2022, A.________ sold 1.65 g of cocaine to an undercover agent. He resisted arrest. A search of his home that same day led to the discovery of 35.57 g of cocaine and other narcotics. The Uster District Court, and subsequently the Zurich Cantonal Court, found A.________ guilty of multiple violations of the Narcotics Act and obstruction of official acts. A.________ appealed to the Federal Supreme Court, arguing that the evidence obtained from the covert investigation and the subsequent search was inadmissible because the covert investigation was illegal. Specifically, he challenged the existence of sufficient suspicion and argued that the measure violated the principles of proportionality and subsidiarity, as other less intrusive measures (such as a search or surveillance) were possible.
Law
The Federal Supreme Court reiterates the distinction between covert investigation (Art. 298a CrimPC) and undercover operations (Art. 285a CrimPC). A covert investigation is a short-term, less intrusive measure where the agent does not use a false identity supported by official documents. An undercover operation is longer, more intensive, requires a documented "legend," and is only authorized for serious offenses listed in a specific catalog and with the approval of the compulsory measures court.
For a covert investigation to be legal, two cumulative conditions must be met (Art. 298b para. 1 CrimPC):
- Sufficient suspicion (lit. a): There must be suspicion that a crime or misdemeanor has been committed. A mere vague suspicion may be sufficient to initiate the measure.
- Subsidiarity (lit. b): Previous investigative efforts must have been unsuccessful, or the investigation would otherwise be doomed to failure or rendered excessively difficult without this measure. This principle gives effect to the principle of proportionality (Art. 197 para. 1 lit. c CrimPC) and requires that alternatives be examined.
Finally, the Federal Supreme Court reiterates that decisions by cantonal authorities must be reasoned (Art. 112 para. 1 lit. b LTF). Insufficient reasoning, which fails to clarify the authority's rationale, constitutes a violation of the right to be heard (art. 29 para. 2 of the Federal Constitution.) and results in the annulment of the decision.
Application to the case at hand
The Federal Supreme Court examined the two conditions for covert investigation:
- Regarding sufficient suspicion: The Federal Supreme Court found this condition to be met. A.________'s behavior on August 9, 2022 (fleeing desperately, jumping into a river, and, most importantly, discarding three separate bags of cocaine) was highly suspicious. This behavior, even for a mere user, suggested drug trafficking activity, justifying the opening of an investigation. The appellant's claim on this point is therefore rejected.
- Regarding subsidiarity: The Federal Supreme Court ruled in favor of the appellant. It deemed the reasoning of the Zurich Cantonal Court to be manifestly insufficient. The lower court relied on general and abstract assertions, such as the claim that a search of a small-time dealer is often fruitless or that surveillance is complex. It failed to explain why, in this specific case, these alternatives were unfeasible. The Federal Supreme Court highlighted a major contradiction: the public prosecutor's office had issued a search warrant on October 27, 2022, four days before ordering the covert investigation. This suggests that the prosecutor initially considered a search to be an appropriate measure. The Cantonal Court did not address this crucial point in its reasoning at all. By failing to provide a concrete and case-specific analysis to justify the use of a covert investigation over other measures, the Cantonal Court violated its obligation to provide reasons and, consequently, the appellant's right to be heard.
Outcome
The Federal Supreme Court granted the appeal. It annulled the judgment of the Zurich Cantonal Court and remanded the case for a new decision. The Cantonal Court must re-examine the issue of the subsidiarity of the covert investigation and provide detailed, substantiated reasoning explaining why alternative measures were not feasible in this specific instance. Costs are to be borne by the Canton of Zurich, which must also pay compensation to the appellant for the federal proceedings.
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