The non-retroactivity of laws in French law

French civil and public law refer primarily to Article 2 of the Civil Code, which states that “The law only applies to the future; it has no retroactive effect.”

In civil law, express mention of retroactivity is required (Cass. Civ. 1st 12/06/2013 No. 12-15.688): “But whereas the new law does not apply, unless retroactivity is expressly decided by the legislature, to legal acts concluded prior to its entry into force.”

Furthermore, the effects of a new law that only applies to the future cannot alter the legal effects of a legal situation that was definitively established at the time of its entry into force (Cass. Civ. 03/06/2021 No. 20-12.353).

In French public law

The principle of non-retroactivity of administrative acts prevents a new rule from being applied in such a way that it would call into question situations already established under the old rules (CE ASS 25/06/1948 Sté du Journal l’Aurore no. 94511; Article L221-4 of the Code of Relations between the Public and the Administration).

The Constitutional Council has ruled that the legislature may not, without sufficient grounds of public interest, undermine legally acquired rights or call into question the effects that may legitimately be expected from such rights (CC No. 2013-682 DC 19/12/2013 §14) or, more broadly, situations arising under previous legislation (CC No. 2019-812 QPC 15/11/2019 §5).

The Council of State refers to the provisions of Article 6 §1 of the European Convention for the Protection of Human Rights and Fundamental Freedoms in ruling that retroactive intervention by the legislature in favor of the State must be based on compelling reasons of general interest.

Furthermore, the non-retroactivity of the law has constitutional value in matters of law enforcement, understood in a broad sense, including administrative sanctions (CC No. 82-155 DC 12/30/1982 and No. 2001-456 DC 12/27/2021 §21).

08/06/2025 – Thierry Clerc