“L’importance d’être… sérieux ?” La lutte contre la fraude au sein des institutions de l’Union

The protection of the financial interests of the EU and by the EU: leading by example?

The protection of financial interests is a crucial issue within the EU.¹ However, given its traditional reliance on the enforcement institutions of the Member States, the effort of the EU has first aimed at enhancing the cooperation between judicial authorities of the Member States, and more recently it concerned the harmonisation of domestic legislation in these matters.² The creation of the European Public Prosecutor’s Office (EPPO) in 2017, made possible by the Treaty of Lisbon, can be seen as a game-changer in this context.³ EPPO is the first trial of a European parquet, with a decentralised structure and a small central unit.

The legal challenge presented here concerns a case bearing a special interest, since it deals with the protection of the financial interests of the EU at the supranational level, i.e., in the perspective of the functioning of the European institutional and administrative machinery.

Indeed, EPPO was investigating a suspect case of fraud allegedly committed by the then-chairman of the European Court of Auditors (ECA). This makes this case both high profile and sensitive, and crucial for the credibility of the EPPO both at the EU and at the domestic level. From another perspective, this case affects the credibility and coherence of the EU as a legal order abiding by the rule of law.

The facts of the case

With this action, EPPO asks the General Court to annul a decision of the audit institution denying its staff the authorisation to be heard as witnesses in the framework of the EPPO’s investigation. More precisely, EPPO requested ECA to lift the confidentiality of EU officials to be heard as witnesses, without success.

EPPO started investigating at the end of 2022, following a report by OLAF, the EU’s anti-fraud office, on a suspected fraud committed by Mr Klaus-Heiner Lehne, a German politician who became Chairman of the audit institution of the EU.

Lehne started its mandate in 2016 as Chairman of ECA with the best intentions, arguing before the Budgetary Committee of the EP that: “People cannot even begin to trust the EU institutions if they do not believe we are looking after their money properly and keeping a good account of how we are doing that.”⁴

The whole story starts in 2021 when the French newspaper Libération reported that Lehne did not comply with residency requirements in Luxembourg during his mandate, though it claimed expatriate allowances,⁵ and that this would amount to fraud. Moreover, Libération claimed Lehne abused expense claims, reporting that he and other senior ECA figures had sold private dinners and tours of the court. Lehne denied all the wrongdoings before the budgetary control committee of the European Parliament, claiming that “The investigation relied essentially on unproven and untrue statements and on a false interpretation of the applicable rules.”⁶

After these revelations, OLAF referred the case to the EPPO, which formally opened an investigation in 2022. Nevertheless, investigators soon encountered strong resistance from the ECA, which, according to the EPPO, consistently obstructed access to critical evidence.

The action: the investigation by EPPO and the contested decision  

In the context of the investigation, the European Parquet asked the Court of Auditors to lift the confidentiality rule of its officials and hear them as witnesses in the framework of the EPPO’s criminal investigation, without success.

In its action seeking the annulment of the decision, EPPO develops five pleas in law: the first one relates to the misuse of power concerning Article 19 of the Staff Regulations. This article is part of the broader framework ensuring confidentiality, loyalty, and integrity in the conduct of EU officials, and establishes that: ‘An official may not, without the permission of the appointing authority, publish or cause to be published, whether alone or with others, any matter dealing with the work of the Union or relating to the activities of the Union. Permission shall be refused only where the proposed publication is liable seriously to prejudice the legitimate interests of the Union.’

In short, ECA denied authorisation to its officials to be heard as witnesses, and this denial is an expression of misuse of powers: according to the EPPO the Court of Auditors relied on reasons other than the need to protect the interests of the Union.

In a second plea, the EPPO contests the Court of Auditors a violation of the duty of sincere cooperation provided for in Article 13(2) TEU. This duty of inter-institutional loyalty and sincere cooperation is the expression of the more general principle of sincere cooperation of Article 4(3) TEU.⁷

The EPPO contests the reiteration of a series of decisions by the audit institution, denying it the possibility to fulfil its mission under Article 86 TFEU, i.e., to investigate criminal offences affecting the Union budget. The European Parquet argues that the denial of the request under Article 19 of the Staff Regulations, and the consequent impossibility for the EPPO to pursue its mission to ‘seek all relevant evidence, whether inculpatory or exculpatory’ amounts to an undue interference with the EPPO’s powers under the Treaties and, therefore, to a violation of the duty of sincere cooperation.

With the third plea in law, the EPPO alleges a breach of the obligation to respect the confidentiality of criminal investigations. The EPPO Regulation provides for in Article 108 an obligation of confidentiality binding prosecutors with respect to any information held by EPPO. This provision also protects investigations carried out under the authority of the EPPO by rules concerning professional secrecy under the applicable Union law, which means that other institutions do not have an unrestricted right of access to the information of the criminal investigation file.

In the view of the EPPO, the Court of Auditors breached this provision, by seeking direct or indirect access to information held by the EPPO in the context of the ongoing criminal investigation – in particular by requesting the organization of meetings at technical level with officials not authorised to know about the criminal investigation; in doing so, the ECA exceeded the limits of its mandate and disregarded its obligations under EU law, in particular, the respect for the confidentiality of criminal investigations.

With the fourth plea in law, the EPPO alleges a violation of its independence in the conduct of criminal investigations. In the interaction between the EPPO and ECA preceding the action before the General Court, EPPO claims that ECA tried to scrutinise the activities of the EPPO. On its side, EPPO argues that criminal investigations are a purely judicial prerogative, lying exclusively with the EPPO and the competent national authorities, inasmuch as the protection of the Union’s financial interests is concerned. With the procedure directing at lifting the confidentiality rule of ECA officials, the audit institution tried to interfere with the investigations by EPPO, arguing that there was no criminal offence, and substituting its own assessment to that of EPPO.

With the fifth plea in law, the EPPO challenges an incorrect application of the Protocol on Privileges and Immunities. The audit institution did not authorise the hearing of witnesses, who do not enjoy immunity under EU law, and whose hearing must be authorised by the institution to which they belong. ECA challenged the approach by the EPPO and argued it was contradictory and refused to cooperate. By refusing to cooperate with the EPPO, in the latter’s view, ECA breached EU law.⁸

The significance of this case for the Union: “O Coherence, Coherence! Wherefore art thou Coherence?”

The relevance of this case can be assessed from multiple perspectives: at the supranational level, at the domestic level, and in a transnational perspective.

First, at the supranational level, several considerations can be made. From a first perspective, this case is relevant for the sound development of the European institutional and administrative machinery. European institutions, bodies, and agencies must all abide by the EU rules and values, as the EU legal order is based on the rule of law, which is a principle of paramount importance for the whole system.⁹ The fight against fraud, and more generally against maladministration, is crucial to this point. It is therefore important for the EU to be coherent in the message it gives to the Member States: the protection of the financial interests of the EU must be a strong prerogative at the supranational level, within EU institutions and agencies. One can lead only by giving the right example.

In this context, another case should be recalled: Frontex, the EU dedicated external borders agency, whose Executive Director resigned in 2022 after allegations of serious violations of the Frontex founding Regulation and maladministration.¹⁰ At this purpose, the scientific debate has investigated whether criminal law should punish top officials of EU institutions, to strengthen the effectiveness of the protection of the rule of law within the Union, in this case declined as protection of the financial interests of the EU.¹¹ Even without digging into these issues, the current legal framework requires that EU offices tasked with the protection of the financial interests of the EU do have the means to carry out their mandate, and do enjoy of the loyal and sincere cooperation of the other European institutions, such as the Court of Auditors.

The facts of this case, as exposed in the action, do reveal a lack of cooperation from the side of the Court of Auditors and a lack of respect for the prerogatives of the EPPO, as stated in Article 4 of the EPPO Regulation. In particular, the founding Regulation endows EPPO of the necessary independence to carry out its functions, and provides that it shall act in the interest of the Union as a whole, as defined by EU law, and neither seek nor take instructions from any person external to EPPO, any institution, who shall respect the independence of EPPO and shall not seek to influence it in the exercise of its tasks.¹² EPPO shall be bound by the principles of the rule of law and proportionality in all its activities.¹³

To this purpose, the material competence of the EPPO is identified with respect of criminal offences affecting the financial interests of the Union and, to this end, the EPPO is endowed with powers to carry out investigations and other measures, and also making requests for the lifting privileges and immunities under Union law.¹⁴

Having regard to the legal framework, it is of paramount importance that the prerogatives of the EPPO are respected by other institutions. Lacking this, the whole reputation of EPPO at the domestic level might be damaged, and this is the second dimension of the significance of this case identified above. At another level, the transnational cooperation instruments are indirectly affected by the manner supranational institutions work and operate, and this is the third level of analysis. Furthermore, it is very important for the credibility of the Union that the fight against fraud in the context of the protection of the financial interests of the Union can take place coherently also toward the institutions of the EU.

The broader perspective: the protection of the financial interests of the EU, conditionality and the rule of law  

In a broader perspective, this case sheds light on the enhanced value of the protection of the financial interests of the EU in the context of one of its existential crises,¹⁵ i.e., the rule of law crisis.

As is known, the protection of the financial interests of the EU has become the ‘Trojan horse’ through which the EU has reshaped its response to the rule of law crisis, with the Conditionality Regulation.¹⁶ This instrument is one of the most significant tools of protection of the financial interests of the EU, together with the Common Provisions Regulation.¹⁷ In recent years, these new tools have reshaped the implementation and governance of one of the most innovative EU instruments, the Next Generation EU.¹⁸ In this perspective, the protection of the financial interests of the EU is evolving itself into a meta-policy, to provide the Union with new teeth to enhance the implementation of EU law in one of its weakest spots, the mechanisms guaranteeing the protection of the founding values of the Union, as defined in Article 2 TEU.

One of the observations that arises here is that the transformation of instruments requires their coherent sound implementation by all institutions; this is crucial to the credibility of the Union, in itself, and also in the perspective of the effort requested by Member States. The connection established by the Court of Justice between the budget of the Union and the principle of solidarity,¹⁹ one of the core general principles of Union law that played a pivotal role in the responses to the last crises,²⁰ demonstrates that the Court is ready to back up the evolutions and transformations of the traditional toolkit of EU law, even when they seem to stretch the boundaries of the EU competences.

For this reason, it is of paramount importance that every institution plays its role with coherence and respect for the implementation of EU law, even when this requires the investigation and, if the case, the exercise of the punitive function toward EU officials. Being coherent is important, and one can lead only by giving the right example.

¹ Directive (EU) 2017/1371 of the European Parliament and of the Council of 5 July 2017 on the fight against fraud to the Union’s financial interests by means of criminal law, OJ L 198, 28.7.2017, p. 29–41. See A. Damato, La tutela degli interessi finanziari tra competenze dell’Unione e obblighi degli Stati membri, Bari, 2018; G. Pizzolante, La lotta alle frodi finanziarie nel diritto penale europeo, Bari, 2019.

² See Articles 82 and 83 TFEU. See C. Amalfitano, Commento artt. 82 e 83 TFUE, in A. Tizzano (a cura di), Le fonti del diritto italiano – Trattati dell’Unione europea, 2a ed., Milano, 2014, pp. 866-910.

³ Art. 86 TFEU enabled the adoption of Council Regulation (EU) 2017/1939 of 12 October 2017 implementing enhanced cooperation on the establishment of the European Public Prosecutor’s Office (‘the EPPO’), OJ L 283, 31.10.2017, pp. 1–71. See K. Ligeti, The European Public Prosecutor’s Office, in V. Mitsilegas, M. Bergström, T. Quintel (eds), Research Handbook on EU Criminal Law, Edward Elgar Publishing, 2024, p. 462‑492; B. Minucci, La Procura europea: uno strumento al servizio dell’effettività della cooperazione giudiziaria in materia penale 295, in Quaderno speciale AISDUE, 2023; R. Belfiore, L’esercizio dell’azione penale da parte dell’EPPO tra legalità e margini di discrezionalità, in Cassazione Penale, 2022, n. 10, pp. 3677-3690; A. Venegoni, L’EPPO nel panorama della cooperazione giudiziaria europea, in Cassazione Penale, 2022, nn. 7-8, pp. 2798-2808; V. Mitsilegas, European prosecution between cooperation and integration: The European Public Prosecutor’s Office and the rule of law, in Maastricht Journal of European and Comparative Law, 2021, vol. 28, n. 2, pp. 245-264; L. Salazar, L’adeguamento interno da parte italiana al regolamento EPPO alla vigilia dell’avvio delle prime indagini, in Sistema Penale, 2021, n. 4, pp. 53-73; H. Herrnfeld, D. Brodowski, C. Burchard (eds.), European Public Prosecutor’s Office: Article-by-Article Commentary, Bloomsbury Publishing, 2020; K. Ligeti, M. Antunes, F. Giuffrida, The European Public Prosecutor’s Office at launch. Adapting national systems, transforming EU criminal law, Wolters Kluwer, 2020; N. Parisi, La Procura europea: un tassello per lo spazio europeo di giustizia penale, Università di Catania – Online Working Paper 2013/n. 48.

⁴ “#Whistleblower: European Court of Auditors must do more to protect those who report fraud within EU institutions”, in EUReporter.co, 13.10.2016. See also the Speech by Klaus-Heiner Lehne, President of the European Court of Auditors, Brussels, 13 October 2016.

⁵ “EU financial watchdog accused of blocking criminal probe”, Euractiv.com, 29.4.2025.

⁶ “European Court of Auditors sued for blocking fraud investigation”, iclg.com, 29.4.2025.

7 F. Casolari, Leale cooperazione tra stati membri e Unione europea, Napoli, 2020.

⁸ Case T-99/25: Action brought on 10 February 2025 – European Public Prosecutor’s Office v Court of Auditors, OJ C, C/2025/2403, 28.4.2025.

⁹ Art 2 TEU. For a recent and significant development on Article 2 TEU, see Opinion of Advocate General Ćapeta, 5 June 2025, case C-769/22, Commission v. Hungary, ECLI:EU:C:2025:408. See G. Di Federico, M. Lanotte, Le conclusioni dell’AG Ćapeta in Commissione c. Ungheria e l’uso a sé stante dell’art. 2 TUE, in Eurojus, 25. 6.2025.

¹⁰ See the special issue guest-edited by L. Marin, S. Nicolosi, M. Gkliati, The external borders of the European Union: Between a rule of law crisis and accountability gaps, in European Law Journal, 2024.

¹¹ A. di Martino, Does the European Union’s rule of law require the criminalisation of EU public officials? A first appraisal, in European Law Journal, 2024, pp. 181-196; A.  di Martino, The Importance of Being a Case. Collapsing of the Law upon the Case in Interlegal Situations, in Italian law journal, 2021, p. 961.

¹² Article 6 EPPO Regulation, in particular Article 6(1), EPPO Regulation.

¹³ Article 5 EPPO Regulation.

¹⁴ Respectively, Article 22, Article 30 ff, Article 29 EPPO Regulation.

¹⁵ Mai’a K. Davis Cross (ed.), Explaining Existential Crises, in The Politics of Crisis in Europe, Cambridge, 2017, p. 22‑53.

¹⁶ Regulation (EU, Euratom) 2020/2092 of the European Parliament and of the Council of 16 December 2020 on a general regime of conditionality for the protection of the Union budget, OJ L 433I, 22.12.2020, pp. 1–10.

¹⁷ Regulation (EU) 2021/1060 of the European Parliament and of the Council of 24 June 2021 laying down common provisions on the European Regional Development Fund, the European Social Fund Plus, the Cohesion Fund, the Just Transition Fund and the European Maritime, Fisheries and Aquaculture Fund and financial rules for those and for the Asylum, Migration and Integration Fund, the Internal Security Fund and the Instrument for Financial Support for Border Management and Visa Policy, OJ L 231, 30.6.2021, p. 159–706.

¹⁸ A. Sandulli, E. Tatì, A. Nato, Introduction to the Special Section: The Shape-Shifting Definition of the EU’s Financial Interest and its Protection in Contemporary Europe, (2025) 2024-3 European Papers-A Journal on Law and Integration 1062‑1066, and the articles of the special issue.

¹⁹ Judgment of the Court (Full Court) of 16 February 2022, Hungary v European Parliament and Council of the European Union, Case C-156/21, ECLI:EU:C:2022:98, para. 129; Judgment of the Court (Full Court) of 16 February 2022, Hungary v European Parliament and Council of the European Union, Case C-156/21, ECLI:EU:C:2022:97, para. 147. See F. Croci, Solidarietà tra Stati membri dell’Unione europea e governance economica europea, Torino, 2020; B. Nascimbene, Il rispetto della rule of law e lo strumento finanziario. La “condizionalità”, in Eurojus, 3/2021, p. 172 ff.; G. Contaldi, Le sentenze della Corte di giustizia sui ricorsi di Polonia e Ungheria e l’emersione del concetto di identità europea, in R. Cisotta, G. Contaldi (eds), Courts, Values and European Identity, Eurojus, 2022. On the principle of solidarity, see K. Lenaerts, S. Adam, La solidarité, valeur commune aux États membres et principe fédératif de l’Union européenne, in Cahiers de droit européen, 2021, p. 307 ss.; G. Morgese, La solidarietà europea: a che punto siamo?, EUSTIC Jean Monnet Chair Working Papers 2023; L. Marin, Solidarity and Crises in the European Union: a constitutional principle in the pandemic and energy crises, Bari, 2024.

²⁰ L. Daniele, P. Simone, C. Venturini, R. Di Marco (eds.), L’Unione europea e le crisi nel mondo contemporaneo, Milano, 2025.