Auditors & Accountants Under Criminal Investigation in Belgium (2026): Who Investigates, When They're Liable and How to Defend

Auditor criminal liability Belgium has moved sharply up the risk agenda for audit partners and senior accountants. Belgium has been progressively reforming its criminal legislation, and a new Criminal Code (nouveau Code pénal / nieuw Strafwetboek) has been adopted to modernise the national framework; its provisions should be checked against the consolidated text as published on the Belgian official gazette portal (eJustice) for the dates on which specific provisions take effect. The combination of a modernised national framework and intensifying cross-border enforcement by the European Public Prosecutor’s Office (EPPO) and the European Anti-Fraud Office (OLAF) has materially widened the exposure of individuals and firms.

This guide takes a clear position: when an investigation touches an auditor, the response must be immediate, coordinated and privilege-aware, hesitation costs more than action. Below you will find who investigates, when liability actually bites, and a decision framework you can apply from the first contact.

At a glance, who can investigate auditors in Belgium

The first mistake firms make is treating every official contact as the same event. It is not. In Belgium an auditor can face a professional disciplinary body, a prudential supervisor, a national criminal prosecutor, and, where EU financial interests are engaged, two separate European bodies. Each has different powers, different notice conventions, and different consequences. Understanding the overlap is the foundation of any competent defence, because the wrong first move in a disciplinary inquiry can prejudice a parallel criminal case, and vice versa.

The Institut des Réviseurs d’Entreprises / Instituut van de Bedrijfsrevisoren (IRE-IBR, the Institute of Registered Auditors) handles professional matters relating to statutory auditors (IRE-IBR), while the College of Supervision of Auditors (Collège de supervision des réviseurs d’entreprises / College van toezicht op de bedrijfsrevisoren), hosted by the Belgian Financial Services and Markets Authority, carries out public oversight, quality inspections and disciplinary functions. The public prosecutor and judicial police run criminal matters. The National Bank of Belgium (NBB) supervises much of the financial sector and can scrutinise auditors of supervised institutions (NBB). At EU level, EPPO prosecutes crimes against the Union’s financial interests (EPPO), while OLAF conducts administrative investigations and refers suspected crimes onward (OLAF).

The table below is the centrepiece of this guide; keep it beside you when the first letter or knock arrives.

Quick takeaways for audit firms

• Identify the authority before responding, powers and risks differ enormously.
• Assume parallel processes: a disciplinary inquiry and a criminal probe can run together.
• Only the prosecutor and EPPO carry criminal exposure; OLAF and peer review feed into it.
• Never surrender documents or make statements before counsel assesses privilege.

When can auditors be criminally liable under Belgian law?

Yes, auditors can be criminally liable in Belgium. Liability does not require that an auditor orchestrated a fraud. It can arise from active participation, from knowingly certifying false accounts, or from culpable complicity where the auditor assisted or failed to prevent an offence they understood to be occurring. The decisive questions are knowledge, intent and the auditor’s causal contribution. Understanding where the thresholds sit is central to assessing auditor criminal liability Belgium exposure before an investigation escalates.

Key offences that attract liability

Several categories of conduct typically generate auditor criminal liability Belgium cases:

• False accounting and fraudulent certification. Signing an audit opinion the auditor knew did not reflect reality. The prosecution must establish the auditor’s awareness or culpable disregard of the misstatement.
• Fraud. Where the auditor participated in a scheme to deceive investors, lenders or the state for gain. Intent to deceive is the core element.
• Complicity. Assisting, facilitating or concealing a principal offence committed by a client. Belgian criminal law treats the accomplice as culpable where they knowingly contributed to the offence.
• Money laundering. Auditors are subject to anti-money-laundering obligations as set out in Belgian AML legislation; failure to report suspicions, or active involvement in disguising criminal proceeds, can found a charge independent of any audit opinion.

Each offence turns on a mental element. Honest professional error, properly documented, is not a crime. The danger zone is where contemporaneous records suggest the auditor saw red flags and proceeded anyway. The exact article numbers applicable to any engagement under scrutiny should be checked against the consolidated text (eJustice).

Modes of liability, individuals vs firms

Belgian law exposes both the individual signing partner and the audit firm as a legal person. Individual liability attaches to the natural person whose conduct satisfies the offence, typically the engagement partner or responsible auditor. Corporate criminal liability, which exists under Belgian law, can attach to the firm where the offence is intrinsically linked to the pursuit of the firm’s objects or committed on its account, which can expose the entity to fines and, in serious cases, measures affecting its ability to operate. Because the interests of the individual and the firm can diverge sharply, separate counsel is frequently required: a defence that protects the firm may implicate the partner, and vice versa.

This conflict must be identified at the outset, not mid-investigation.

Burdens of proof and evidentiary issues in Belgium

The prosecution bears the burden of proving the offence, including the mental element. The evidentiary battleground for auditors is documentary: workpapers, review notes, engagement correspondence, internal emails and quality-control records. These materials can be admissible in criminal proceedings (FPS Justice; Court of Cassation). Because an auditor’s own file so often decides the case, the integrity and completeness of documentation, and the handling of it once a probe begins, is the single most important defensive asset.

Triggers and red flags that typically prompt investigations

Investigations rarely arrive without warning signs. The firms that fare best are those that recognise the red flags early and escalate internally before an external authority acts. Treat any of the following as a prompt to review the engagement file and consider protected legal advice.

Auditor workpaper issues, whistleblower complaints, unusual transactions, client insolvency

• Workpaper gaps or inconsistencies. Missing support for a key judgement, or review notes that contradict the final opinion, are classic triggers for both disciplinary and criminal scrutiny.
• Whistleblower complaints. Internal or external reports, from staff, clients or third parties, frequently seed oversight inquiries and prosecutor referrals.
• Unusual or round-sum transactions. Patterns consistent with concealment or laundering engage the auditor’s AML obligations and any failure to report.
• Client insolvency or collapse. Insolvency practitioners, creditors and the prosecutor routinely examine the last clean audit opinion when a company fails suddenly.
• Regulatory referral. An NBB inspection of a supervised entity can turn into a referral of the auditor (NBB).
• Quality inspection findings. Adverse quality-assurance outcomes can cascade into a disciplinary or criminal track.

Immediate defensive actions, searches, preservation and counsel

The first 24 hours shape the entire case. A search of an audit firm in Belgium is lawful where executed under a valid judicial warrant, and it can occur without notice. Panic, improvised cooperation, and well-meaning but unadvised disclosure are the most common and most damaging errors. The position is unequivocal: stabilise, call counsel, and do nothing irreversible before advice arrives.

On-site search checklist, do’s and don’ts

• Do call your designated criminal counsel and senior partner immediately; note the exact time investigators arrived.
• Do ask to see the warrant and record its scope, the authority named, and the officers present.
• Do assign a staff member to accompany officers and log everything they access, copy or remove.
• Do keep the search team confined to the warrant’s scope and object, politely and on the record, to anything beyond it.
• Don’t destroy, move, alter or “tidy” any document or device, this risks a separate, grave offence.
• Don’t volunteer explanations, answer substantive questions, or hand over passwords without legal advice.
• Don’t let staff give informal statements in corridors; route all contact through the logged point person.
• Don’t notify the client under investigation in a way that could be construed as tipping off.

Interview and rights management

Anyone invited for interview, or questioned on-site, has rights that must be exercised deliberately. The default advice for any person at risk is to secure counsel presence before answering substantive questions. The distinction between a witness and a suspect matters: suspects questioned in Belgium are, in principle, entitled to be informed of their rights and to legal assistance in accordance with the Code of Criminal Procedure, and the right to silence should be understood before, not during, questioning (FPS Justice). Instruct staff not to speculate, not to fill silences, and to defer to counsel on anything touching the engagement.

Evidence preservation and ESI protocol

Impose an immediate legal hold. Suspend auto-deletion, preserve email and workpaper systems, and arrange forensic imaging with a documented chain of custody so the firm’s own records remain admissible and unimpeachable (Court of Cassation).

Defence strategies in criminal proceedings and parallel disciplinary processes

A competent approach to audit firm criminal defence in Belgium is never a single track. The reality is parallel processes, a criminal file and a professional disciplinary matter, sometimes alongside an NBB review, each with its own timetable and disclosure logic. Managed well, they reinforce one another. Managed badly, a statement made to satisfy the disciplinary body becomes the prosecution’s best evidence.

Coordinating criminal defence with the disciplinary response

The disciplinary track typically moves faster and demands document production and explanations earlier than the criminal track (IRE-IBR). That creates a trap: candid submissions to the professional bodies can be obtained and used in the criminal case. The right approach is a single coordinated strategy in which criminal and disciplinary counsel share a defence theory, align on what is disclosed and when, and manage waiver risk deliberately. Never let the disciplinary response run ahead of the criminal analysis.

Privilege, legal professional secrecy, and client confidentiality

This is where firms most often misjudge their position. In Belgium, legal professional privilege protects communications with lawyers, advice sought and given, not the audit work product itself. Audit workpapers are generally not privileged and can be compelled and used in evidence. That distinction is decisive: legal advice taken through counsel on how to respond to an investigation is protected; the engagement file is not. To create protected space, sensitive assessments of exposure should be conducted through legal counsel as part of an internal investigation, rather than circulated as ordinary firm correspondence. Third-party production requests and regulator requests should always be routed through counsel so that privilege, where it exists, is asserted and not inadvertently waived.

Tactical options, challenge jurisdiction, exclude evidence, negotiate, internal review

The realistic defensive levers are: challenging the competence or jurisdiction of the investigating body (particularly where EPPO or OLAF involvement is questionable); seeking to exclude evidence obtained outside a warrant’s scope or through procedural defect; negotiating resolution where the evidential picture is adverse; and conducting a protected internal investigation to establish the facts before committing to a position.

Cross-border investigations: EPPO and OLAF, what changes for audit firms

When EU money is in play, the investigatory landscape changes. EPPO has competence over crimes affecting the Union’s financial interests under Regulation (EU) 2017/1939 (EUR-Lex; EPPO), and OLAF conducts administrative investigations into fraud against the EU budget, referring suspected crimes to national prosecutors or EPPO (OLAF). For auditors, this is most relevant where clients receive EU grants or operate in sectors exposed to EU funding.

Cooperation requests, evidence transfer and EU instruments

Cross-border probes rely on cooperation between authorities and on evidence moving between member states. For an audit firm this means documents produced in one jurisdiction can surface in proceedings in another, and that the firm’s handling of EU-grant files must preserve chain of custody. Where OLAF’s administrative remit meets EPPO’s criminal competence, the referral point is critical, it is where administrative findings can convert into criminal exposure.

Practical coordination with multinational clients and counsel

Firms with multinational clients should instruct counsel capable of coordinating Belgian and EU-level strategy, maintain a single factual record across jurisdictions, and avoid inconsistent responses to parallel requests. Early mapping of which authority is competent, and whether that competence can be challenged, is the most valuable step a firm can take in a cross-border matter.

Sanctions matrix and likely outcomes, criminal, administrative, disciplinary

Auditor sanctions in Belgium span three regimes that can apply cumulatively. The practical consequence most firms underestimate is the knock-on effect: a disciplinary suspension or removal from the register can end a career independent of any criminal verdict, and a criminal conviction can trigger loss of licence and jeopardise professional indemnity cover.

The recommended sequencing is to stabilise the criminal exposure first, because its outcome and admissions cascade into the other regimes, then manage the disciplinary and administrative tracks on a coordinated timetable that avoids self-incrimination.

Practical compliance and risk-reduction checklist for audit firms

Prevention is cheaper and more effective than defence. The strongest protection against auditor criminal liability Belgium exposure is built before any investigation, in documentation discipline, response readiness and training.

• Documentation and retention. Maintain complete, contemporaneous workpapers; never backfill or amend files after a concern arises.
• Incident response plan. Have a written search protocol, a named response team, and counsel on call.
• Internal review triggers. Define events, whistleblower reports, regulator contact, client collapse, that mandate immediate protected legal review.
• Engagement letters. Ensure scope, responsibilities and reliance are clearly recorded for every engagement.
• AML discipline. Keep reporting decisions documented; a well-evidenced reporting trail is a strong defence.
• Training. Rehearse searches and interviews so staff know not to improvise, delete or volunteer information.
• Quality control. Act on and document remediation of inspection and internal QC findings.

How to choose counsel and handle insurer notification

Appoint criminal counsel the moment any formal contact, warrant, interview request or asset-freezing occurs; appoint disciplinary counsel when a professional body opens an inquiry. Because the firm and its partners can have divergent interests, run conflicts checks early and be prepared to instruct separate representation. Notify your professional indemnity insurer promptly, most policies require early notification of circumstances that may give rise to a claim, and late notice can jeopardise cover. Treat the insurer notification itself as a document to be prepared with counsel, because its wording can bind you. For practitioners mapping their options, our white-collar crime lawyer, Belgium hiring guide and the profile and contact page for our practice head are the right starting points.

Conclusion, tactical summary and next steps

Auditor criminal liability Belgium is now a live, escalating risk, and the firms that survive an investigation are those that act decisively in the first hours. The clear recommendation is to treat any authority contact as serious until proven otherwise, protect your documents and your people, and run a single coordinated strategy across every parallel process. Take these five actions: (1) identify which authority is involved and whether its competence can be challenged; (2) call criminal counsel and impose a legal hold immediately; (3) separate individual and firm defence where interests diverge; (4) notify your insurer with counsel’s input; and (5) manage disciplinary and administrative tracks without prejudicing the criminal case.

Review your readiness now, do not wait for the knock. For a preparedness assessment or urgent defence support on auditor criminal liability Belgium matters, contact our practice head via the profile page.

Sources

1. Belgian e-Justice, legislation portal (Moniteur Belge / consolidated laws)
2. Institut des Réviseurs d’Entreprises / Instituut van de Bedrijfsrevisoren (IRE-IBR)
3. National Bank of Belgium (NBB)
4. European Public Prosecutor’s Office (EPPO)
5. European Anti-Fraud Office (OLAF)
6. EUR-Lex, Regulation (EU) 2017/1939 (establishing the EPPO)
7. EUR-Lex, Regulation (EU) 537/2014 (EU audit regulation)
8. Belgian Federal Public Service Justice (FPS Justice)
9. Court of Cassation (Belgian Supreme Court)