Judgment of the Court (Grand Chamber) of 5 March 2024.#Défense Active des Amateurs d’Armes ASBL and Others v Conseil des ministres.#Request for a preliminary ruling from the Cour constitutionnelle.#Reference for a preliminary ruling – Approximation of laws – Directive 91/477/EEC – Control of the acquisition and possession of weapons – Firearms prohibited or subject to authorisation – Semi-automatic firearms – Directive 91/477, as amended by Directive (EU) 2017/853 – Article 7(4a) – Power of Member States to confirm, renew or prolong authorisations – Presumed impossibility of using that power in respect of semi-automatic firearms converted to fire blanks or into salute or acoustic weapons – Validity – Article 17(1) and Articles 20 and 21 of the Charter of Fundamental Rights of the European Union – Principle of the protection of legitimate expectations.#Case C-234/21.