Constitutional Court Strikes Down Amendments That Would Have Removed ZFE and Relaxed ZAN

Overview

• The Conseil constitutionnel on 21 May annulled totally or partially 25 articles of the so‑called simplification law, including provisions that would have deleted Zones à Faibles Émissions (ZFE) and loosened Zero Artificialisation Nette (ZAN) limits.
• The court's decision rested on the 'cavalier législatif' doctrine, meaning the contested amendments were judged unrelated to the original purpose of the bill rather than being ruled on their policy merits.
• Right‑wing and far‑right MPs immediately signalled plans to pursue a new, dedicated bill to achieve the same policy goals without the procedural flaw, while environmental groups and left parties hailed the ruling as a win for health and nature.
• Local authorities that would be affected by a reinstated ZFE say they may need extra resources and legal clarity to implement or re‑activate restrictions on the most polluting vehicles, a concern for low‑income households that cannot easily replace cars.
• The case highlights longer debates: ZFE were introduced from 2019 and extended in 2021 to cut deadly air pollution, ZAN is a 2050 land‑use goal, and the episode exposes tensions over omnibus laws that became a vehicle for unrelated policy rollbacks.