Federal Supreme Court, 20.02.2025, 1C_236/2024 (BGE 151 I 32)
Facts
On March 27, 2024, the Solothurn Cantonal Council approved a commitment credit of 20.2 million francs for the renovation of Baselstrasse and the construction of a second railway track at St. Katharinen. Marianne Wyss challenged this decision before the Federal Supreme Court, arguing that the credit should have been subject to a mandatory referendum.
Legal Analysis
Article 34 of the Constitution guarantees political rights and mandates adherence to the referendum mechanisms established by cantonal law. Under the Solothurn Constitution, any single expenditure exceeding 5 million francs must be submitted to a mandatory referendum, while an optional referendum applies to amounts starting at 1 million francs. However, a special rule exists for road projects: Section 8ter, paragraph 4 of the Cantonal Roads Act stipulates that only road projects exceeding 25 million francs are subject to an optional referendum.
The Federal Supreme Court reiterated two essential principles:
- the principle of unity of subject matter prohibits the artificial splitting of a project or the aggregation of heterogeneous elements to circumvent a referendum;
- railway infrastructure cannot be classified as "road projects" under the cantonal law, as they are governed by a separate regulatory framework, notably requiring approval from the Federal Office of Transport (FOT).
Application to the case
The total credit included 5.54 million francs specifically allocated to railway facilities. This amount alone exceeds the 5-million-franc threshold set by the Solothurn Constitution for triggering a mandatory referendum. Even though the project was designed as a single entity, the inclusion of a distinct railway component required the entire credit to be submitted to a mandatory referendum. The Federal Supreme Court therefore upheld the appeal and mandated this procedure.
