Case C-947/26 P, Court of Auditors v EPPO – when one EU institution will not let its staff testify
The Union created a prosecutor to investigate fraud against its budget. This appeal is about what happens when the institution under investigation is itself one of the Union’s own.
Facts
On 14 July 2022 the European Anti-Fraud Office reported to the European Public Prosecutor’s Office possible irregularities in the recruitment and establishment of a person who had become an official of the European Court of Auditors. The EPPO opened an investigation in December 2022 and, over the following year and a half, asked the Court of Auditors repeatedly to lift the inviolability of its premises and archives and the immunity of the persons under investigation; the Court of Auditors’ President replied that the information supplied did not allow him to agree. On 26 September 2024 the delegated prosecutor asked the Court of Auditors, under Article 19 of the Staff Regulations, to lift the duty of confidentiality of twelve current and former officials so that they could be heard as witnesses. Article 19 forbids an official to disclose in legal proceedings information known by reason of his duties without permission, and provides that “permission shall be refused only where the interests of the Union so require”. By letter of 9 December 2024 the Court of Auditors refused. On 10 June 2026 the General Court (Fourth Chamber, extended composition) annulled that refusal in Case T‑99/25 (ECLI:EU:T:2026:380). The Court of Auditors appeals on five grounds, asking the Court to dismiss the EPPO’s action as inadmissible or, in the alternative, as unfounded.
Grounds of Appeal
According to the Official Journal notice, the appellant relies on five grounds of appeal.
By the first ground of appeal, the Court of Auditors claims that the General Court erred in law by classifying the Court of Auditors’ position on the EPPO’s request of 26 September 2024 to lift the confidentiality obligations of 12 current and former staff members as a challengeable act for the purposes of an action under Article 263 TFEU. Furthermore, the General Court distorted the Court of Auditors’ arguments concerning the absence of a challengeable act and breached its obligation to state reasons with regard to the Court of Auditors’ argument that no decisions under Article 19 of the Staff Regulations had been adopted.
By the second ground of appeal, the Court of Auditors claims that the General Court erred in law by enlarging the scope of the fifth plea to include an alleged infringement of Article 19 of the Staff Regulations, a plea that had not been raised in the application. The General Court distorted the arguments raised by the parties in the context of the fifth plea. By reconstructing and enlarging the scope of that plea, the General Court also infringed the Court of Auditors’ rights of defence.
By the third ground of appeal, the Court of Auditors claims that the General Court distorted the content of the contested statement of position by stating that the Court of Auditors had merely found that, since it had not granted the request to lift the immunity of the persons under investigation, it was also entitled not to accept the request to lift the duty of confidentiality of the 12 officials whom the EPPO intended to hear as witnesses. The General Court unduly disregarded the other arguments put forward by the Court of Auditors and infringed its obligation to state reasons.
By the fourth ground of appeal, the Court of Auditors claims that the General Court erred in law in its interpretation of the principle of mutual sincere cooperation within the meaning of Article 13(2) TEU and breached its obligation to state reasons. The General Court’s findings disregard the fact that the duty of sincere cooperation is not a unilateral obligation to grant requests without obtaining the information necessary to enable the institution concerned to understand to what extent criminal offences falling within the competence of the EPPO may potentially have been committed in the case under investigation and how the officials listed in a request under Article 19 of the Staff Regulations would be able to contribute to establishing the existence of such crimes.
By the fifth ground of appeal, the Court of Auditors claims that the General Court erred in law in its interpretation of the first paragraph of Article 19 of the Staff Regulations. The reasoning of the General Court excludes, by default, the very possibility that the lifting of confidentiality obligations for the purposes of an EPPO investigation could be contrary to the requirements of the interests of the Union, and obliges the institution concerned to grant the EPPO’s request without obtaining the information necessary to assess a possible infringement of those interests.
Sources
OJ notice C/2026/4950 (EUR‑Lex) · Case file on CURIA · Judgment under appeal, T‑99/25 (ECLI:EU:T:2026:380) · Regulation (EU) 2017/1939 (EPPO)
Comment
The fifth ground states the question in its sharpest form. Article 19 makes refusal the exception: permission “shall be refused only where the interests of the Union so require”. The Court of Auditors reads that as giving it a judgment to exercise, and a judgment cannot be exercised blind — it needs to know enough about the investigation to say whether the Union’s interests are engaged. The General Court’s reading, on the appellant’s account, is that the Union’s interests cannot in principle be harmed by its own prosecutor investigating offences against the Union’s budget, so that the institution has nothing to weigh. Between those two positions lies the whole relationship between the EPPO and the bodies it investigates.
The fourth ground carries the institutional argument. Article 13(2) TEU requires the institutions to “practice mutual sincere cooperation”, and the Court of Auditors says that is a two-way duty: the EPPO cannot simply demand, it must inform. The difficulty with that position is the one the background makes plain. Over eighteen months the Court of Auditors declined to lift immunity and inviolability on the ground that it had not been told enough, and proposed to inform the persons under investigation before deciding — which a prosecutor is unlikely ever to accept. A duty of cooperation that lets the investigated institution set the conditions on which it can be investigated is hard to reconcile with an independent prosecutor, and that is presumably what persuaded the General Court.
The first ground may still decide the appeal without reaching any of this. A refusal to lift confidentiality, the Court of Auditors argues, was a “statement of position” and not a decision under Article 19 at all, and so not open to challenge under Article 263. If the Court agrees, the EPPO is left with no judicial route against an institution’s refusal to cooperate — which is itself a striking result for a body created to ensure that fraud against the Union does not go uninvestigated because the national authorities, or here the Union’s own, decline to help.
Whatever the outcome, this is the first time the Court of Justice will have to say how the EPPO’s powers apply when the target is inside the Union’s institutional structure rather than outside it. The EPPO was designed with Member States’ authorities in mind. The Court of Auditors — the Union’s own guardian of financial propriety — may be the institution that tests whether it also works at home.