Judgment — ECLI:EU:C:2017:803
Date: 2017-10-25
Language of the case: English
Court formation: Grand Chamber
Subject matter: External relations;Provisions governing the Institutions;International agreements
Procedure: Action for annulment - successful

Summary — Judgment of the Court (Grand Chamber), 25 October 2017 1. Judicial proceedings — Intervention — Pleas different from those of the main party supported — Admissibility — Condition — Connection with the subject-matter of the case (Statute of the Court of Justice, Art. 40; Rules of Procedure of the Court of Justice, Arts 129 and 132(2)(b)) 2. Acts of the institutions — Procedure for adopting — Rules laid down in the Treaties— Mandatory nature — Practice of an institution as to the legal form of a decision — Not relevant in the light of the rules laid down in the Treaty (Arts 218(9) TFEU and 288 TFEU) 3. Acts of the institutions — Indication of the legal basis — Obligation — Scope — Decision of the Council establishing the position to be adopted on the Union’s behalf in a body set up by an international agreement — Effect of there being no indication of the legal basis (Art. 5(2) TEU; Art. 218(9), TFEU and 296 TFEU) 4. Acts of the institutions — Indication of the legal basis— Obligation — Scope — Omission not constituting a substantial defect — Limits — Express reference indispensable to the exercise of judicial review (Art. 296 TFEU) 1. See the text of the judgment. (see para. 23) 2. In so far as the rules regarding the manner in which the EU institutions arrive at their decisions are laid down in the Treaties and are not within the discretion of the Member States or of the institutions themselves, the Treaties alone may, in particular cases, empower an institution to amend a decision-making procedure established by the Treaties. In that context, the practice of the institutions, and, in particular, an alleged consistent practice in relation to the preparation of the Union’s position, in accordance with Article 218(9) TFEU, by means of conclusions cannot alter the rules of the Treaties that the institutions are obliged to respect. A mere practice on the part of the Council cannot derogate from the rules of the Treaty and cannot therefore create a precedent that is binding on the EU institutions. Further, the fact that an institution of the European Union derogates from the legal form laid down by the Treaties constitutes an infringement of essential procedural requirements that is such as to require the annulment of the act concerned, since that derogation is likely to create uncertainty as to the nature of that act or as to the procedure to be followed for its adoption, thereby undermining legal certainty. That applies when the wording used in the contested act adds to that uncertainty, in that the wording is incompatible with the requirement that a decision of an EU institution under Article 288 TFEU must be binding and there is nothing in the contested act to suggest that the Member States are obliged to adopt a position on the Union’s behalf, contrary to what is provided in Article 218(9) TFEU. (see paras 41, 42, 44, 46) 3. An indication of the legal basis is essential in the light of the principle of the allocation of powers enshrined in Article 5(2) TEU, according to which the European Union must act within the limits of the competences conferred on it by the Member States in the Treaties to attain the objectives set out in the Treaties with respect to both the internal action and international action of the European Union. The choice of the appropriate legal basis has constitutional significance, since, having only conferred powers, the European Union must link the acts which it adopts to provisions of the FEU Treaty which actually empower it to adopt such acts. Further, the indication of the legal basis is of particular significance in order to preserve the prerogatives of the EU institutions concerned by the procedure for the adoption of a measure. Moreover, an indication of the legal basis is essential in the light of the obligation to state reasons that stems from Article 296 TFEU. That obligation, which is justified in particular by the need for the Court to be able to exercise its power of judicial review, must apply to all European Union acts that produce legal effects. Last, the requirement of legal certainty means that the binding nature of any act intended to have legal effects must be derived from a provision of EU law which prescribes the legal form to be taken by that act and which must be expressly indicated therein as its legal basis. As regards a decision establishing the positions to be taken on the Union’s behalf, in accordance with Article 218(9) TFEU, a failure to indicate the legal basis and a derogation from the legal form laid down by that provision are the source of confusion as to the legal nature and scope of that act and as to the procedure that has to be followed for its adoption, a confusion that is apt to weaken the European Union in the defence of its position. (see paras 48-50, 52, 53, 58) 4. While it is true that failure to refer to a specific provision of the Treaty need not necessarily constitute an infringement of essential procedural requirements if the legal basis for a measure may be determined from other parts of the measure, such explicit reference is, however, indispensable where, in its absence, the parties concerned and the Court are left uncertain as to the specific legal basis. Where the legal basis of the contested act cannot be clearly determined, the failure, in that act, to indicate any legal basis cannot be regarded as a purely formal defect. (see paras 55, 57)