Federal Supreme Court, 15.10.2025, 1C_710/2024
Facts
The appellant, owner of a building located in a protected site zone (in the city of Lucerne), replaced windows without a permit. Following a formal notice, she filed an application for a retroactive building permit. By decision of October 26, 2022, the City of Lucerne:
- partially authorized the replacement of the windows (1st to 3rd floor),
- imposed corrective measures to restore the historical appearance of the facade, including:
- two thin horizontal transoms,
- solid base panels with plastic profiling,
- a 10 mm protruding astragal (meeting stile).
The Cantonal Court upheld the decision (29.10.2024). Appeal to the Federal Supreme Court.
Law
The right to be heard (Art. 29 para. 2 of the Constitution) allows for the refusal of evidence based on non-arbitrary anticipatory assessment. Internal documents with no probative value are not subject to file access. The Federal Supreme Court rejects the claims of violation of the right to be heard. The cantonal court was entitled to dismiss investigative measures (comparative files, expert reports, witnesses) through anticipatory assessment; the internal opinion of the monument protection authority did not grant a right to consultation. (consid. 3).
Classification of the decision. A restoration order is only issued if a retroactive building permit is refused. Combining the granting of a permit with a restoration order is contradictory. The decision must be interpreted as a refusal of the permit for the existing state, accompanied by an order for compliance. The city effectively refused the retroactive building permit for the installed windows and ordered restoration measures. This interpretation is necessary to resolve the formal contradiction. (consid. 4.3).
Condition of Article 36 of the Constitution:
Suitability. The public interest in regulatory compliance and the protection of urban orthophotography is recognized. The prescribed measures are appropriate for safeguarding this interest. (consid. 4.5.3–4.5.4)
Necessity and proportionality stricto sensu. The appellant proposed a less intrusive alternative: reinstalling the original windows (which had been preserved). The Cantonal Court dismissed this option with insufficient reasoning. If reinstallation restores the historical appearance without violating other rules, the authority must seriously examine it as an equivalent and milder restorative measure. (consid. 4.5.5).
Outcome
Appeal allowed. The cantonal judgment is set aside and the case is remanded to the City of Lucerne to examine the reinstallation of the original windows as a proportionate alternative to restoration. No costs; compensation of CHF 3,000 to be paid to the appellant; case remanded to the Cantonal Court for a new allocation of costs and legal fees for the cantonal proceedings.
Silex newsletter published in collaboration with Daniel Hirschi-Duckert, Attorney at Law
