When May the Tax Authority Inspect Your Bank Account?
I. Introduction: The Tension Between Fiscal Efficiency and Financial Privacy
Few questions in modern tax law are as structurally revealing as this: when a revenue authority demands that a bank disclose a taxpayer’s account records, and the bank refuses — who bears the legal consequence?
The question is deceptively simple. Its resolution, however, requires navigating a collision between two statutes of equal rank, the constitutional architecture of privacy rights, and the doctrinal foundations of banking confidentiality as a species of professional secrecy. In its judgment of April 5, 2024, the Voivodeship Administrative Court (WSA) in Opole confronted precisely this constellation of issues — and reached a conclusion that may reshape the operational boundaries of Poland’s National Revenue Administration (Krajowa Administracja Skarbowa, hereinafter “KAS”) for years to come.
At issue was whether a bank could lawfully decline to comply with a written demand from the head of a customs and fiscal office (naczelnik urzędu celno-skarbowego) for account records of a natural person, where the underlying criminal fiscal investigation had not yet progressed beyond the in rem phase — that is, where no formal charges had been brought against the account holder. The court held that it could, and indeed that it must.
The reasoning deserves close examination, not merely for its doctrinal sophistication, but for the broader principle it articulates: that general competence-granting provisions in organizational statutes cannot, standing alone, override the specific substantive conditions under which banking secrecy may be lifted.
II. Statutory Framework: Two Provisions, One Irreconcilable Divergence
A. The KAS Act: A Broadened Mandate
Article 48(1) of the Act of November 16, 2016, on the National Revenue Administration — as amended effective July 1, 2022 — empowers the head of a customs and fiscal office to issue a written demand to a bank for detailed financial information concerning a natural person. The scope of permissible disclosure is extensive: it encompasses account balances, transaction histories, the dates and amounts of individual credits and debits, transaction descriptions, and the identities of counterparties. This authority operates within the framework of the broader customs and fiscal audit regime.
Critically, the amended provision employs the formulation “natural person” and “activity of a natural person” — conspicuously omitting any reference to “suspect” or any requirement that the individual be the subject of formal charges. The legislative history confirms that this was deliberate: the explanatory memorandum accompanying the amending legislation (Parliamentary Print No. 1532, Sejm of the 9th Term) expressly states that the objective was to enable revenue authorities to obtain banking information during the in rem phase of preliminary investigations — before the person under scrutiny becomes aware of the proceedings.
Non-compliance carries a financial penalty of up to PLN 10,000, imposed by administrative decision pursuant to Article 48(11) of the KAS Act.
B. The Banking Law: A Narrower Gate
Article 105(1)(2)(e) of the Act of August 29, 1997 — the Banking Law — likewise imposes on banks an obligation to disclose information constituting banking secrecy upon demand of the head of a customs and fiscal office. However, it conditions this obligation on compliance with the “rules and procedures set forth in the provisions of the KAS Act” and, crucially, requires that the disclosure arise “in connection with pending criminal proceedings or proceedings concerning fiscal offenses against a natural person who is a party to a contract with the bank.”
The operative phrase — against a natural person — presupposes the in personam phase of criminal proceedings, which under Polish procedural law requires the formal presentation of charges. In the absence of such charges, the statutory predicate for disclosure under the Banking Law is not satisfied.
C. The Legislative Omission
The divergence is neither subtle nor ambiguous. When the legislature amended Article 48(1) of the KAS Act in 2021 to extend disclosure authority to the in rem phase, it neglected to make a corresponding amendment to the Banking Law. The result is a normative collision: the KAS Act authorizes what the Banking Law prohibits.
III. The Factual Matrix
The dispute before the WSA in Opole arose from a demand issued in March 2023 by the Head of the Opole Customs and Fiscal Office to a major Polish bank. Acting pursuant to Article 48(1)(1)–(2) of the KAS Act, and in connection with a preliminary investigation under Article 110a § 1 of the Fiscal Penal Code concerning acts committed within the scope of activity of a natural person (“A.U.”), the official demanded disclosure of all account records for the calendar year 2022 — including balances, transaction flows, counterparty data, and transaction descriptions.
The bank declined. In a written response dated March 23, 2023, it invoked Article 105(1)(2)(e) of the Banking Law, observing that the demand failed to establish whether the investigation had progressed to the in personam phase — that is, whether criminal charges had been brought against the account holder. The bank requested that the customs and fiscal office demonstrate, “in a clear and unambiguous manner,” that the statutory prerequisites under the Banking Law had been met. This response exemplifies the kind of principled engagement with fiscal authorities that characterizes effective dispute resolution with the tax authority.
The official’s response was not dialogue but sanction: on July 11, 2023, the Head of the Opole Customs and Fiscal Office imposed a financial penalty of PLN 8,000 on the bank. The Director of the Fiscal Administration Chamber in Opole upheld the penalty on appeal.
IV. The Court’s Analysis
The WSA in Opole allowed the bank’s complaint, annulling both the appellate and first-instance decisions. Notably, the court did so on grounds different from those advanced by the complainant — exercising its authority under Article 134 § 1 of the Law on Proceedings Before Administrative Courts (PostAdmU), which permits the court to resolve the matter beyond the scope of the pleaded objections.
A. The Procedural Argument: Rejected
The bank had contended that the demand should have taken the form of a formal order (postanowienie) rather than a written request, arguing that this procedural deficiency deprived it of the right to lodge an interlocutory appeal under Article 302 § 1 of the Code of Criminal Procedure, read in conjunction with Article 11 § 1 of the Fiscal Penal Code.
The court disagreed. It held that the “demand” mechanism under Article 48(1) of the KAS Act constitutes an autonomous procedural instrument, situated outside the framework of fiscal criminal proceedings and governed exclusively by the KAS Act’s own provisions. Written form suffices; no formal order is required. However, the court emphasized that this procedural design does not leave the bank without remedy: the statutory right to challenge the penalty decision through administrative appeal — and ultimately through judicial review — provides adequate protection for both the bank’s institutional interests and the privacy rights of banking secrecy beneficiaries.
B. The Substantive Argument: Sustained on Different Grounds
The core of the court’s reasoning addressed the normative collision between the KAS Act and the Banking Law. Three mutually reinforcing lines of argument supported the conclusion.
1. Lex Specialis
The court characterized Articles 104(1) and 105(1)(2)(e) of the Banking Law as lex specialis in relation to Article 48(1) of the KAS Act. The reasoning proceeds from a structural observation: the Banking Law provides a comprehensive, self-contained regime governing banking secrecy — defining its scope, its beneficiaries, its exceptions, and the consequences of its breach. This regime constitutes substantive law (prawo materialne). The KAS Act, by contrast, is an organizational statute (ustawa ustrojowa) establishing the competences, procedures, and operational modalities of revenue authorities. Its provisions are procedural in character (prawo procesowe).
The court invoked the well-established principle that procedural law serves a subordinate, instrumental function in relation to substantive law: it cannot, through the establishment of procedures and operational rules, expand the substantive rights or obligations created by the governing substantive legislation. Applied to the case at hand, this means that the KAS Act — however broadly it may define the procedural authority of customs and fiscal offices — cannot override the substantive conditions under which banking secrecy may be lifted as defined by the Banking Law.
2. The Second-Order Collision Rule
The court acknowledged that the KAS Act, in its current form, is lex posterior — the relevant provision having entered into force on July 1, 2022, whereas the Banking Law dates to January 1, 1997. Under normal circumstances, the later statute would prevail over the earlier one (lex posterior derogat legi priori).
However, the court applied the second-order collision rule: lex posterior generalis non derogat legi priori speciali — a later, more general provision does not abrogate an earlier, more specific one. Since the Banking Law’s provisions on banking secrecy are narrower in scope and more precisely calibrated than the KAS Act’s general competence provisions, the Banking Law retains priority notwithstanding its earlier date of enactment.
This analysis effectively dismantled the position advanced by the customs and fiscal office, which had argued — with considerable vigor — that the chronological priority of the KAS Act should be dispositive.
3. Pro-Constitutional Interpretation and the Restrictive Construction of Exceptions
The most doctrinally significant portion of the judgment draws on constitutional jurisprudence to establish an interpretive framework that decisively favors the bank’s position.
The court invoked the Constitutional Tribunal’s landmark rulings in Cases K 21/96 (June 24, 1997) and K 4/04 (June 20, 2005), as well as the Supreme Court’s resolution in Case I KZP 4/06 (May 23, 2006), to establish the following propositions:
Banking secrecy as a constitutional guarantee. Banking secrecy is not merely a statutory obligation; it functions as one of the institutional guarantees of the constitutional right to privacy under Article 47 of the Polish Constitution, the right to informational autonomy under Article 51, and the corresponding protections afforded by Article 8 of the European Convention on Human Rights and Articles 7 and 8 of the Charter of Fundamental Rights of the European Union.
The maximalist principle. The scope of banking secrecy is defined according to the principle of maximization: all information relating to banking transactions, the persons engaging in such transactions, and the very fact that a transaction has occurred falls within its protective ambit. This principle, articulated by the Supreme Court and endorsed by the academic literature, reflects the foundational role of banking confidentiality in sustaining public trust in the financial system — a role that operates analogously to the principle of resolving doubts in favor of the taxpayer in fiscal matters.
Strict construction of exceptions. Exceptions to banking secrecy must be interpreted restrictively. Extensive or analogical interpretation is constitutionally impermissible. Where doubt exists as to the scope of an exception, it must be resolved in favor of privacy protection.
The precision requirement. The Constitutional Tribunal has repeatedly held that legislative provisions restricting constitutional rights and freedoms must be characterized by “adequate precision and clarity” (należyta precyzja i jasność). This requirement is functionally linked to the principles of legal certainty, security, and the protection of legitimate expectations. A provision that purports to extend the scope of permissible intrusion into banking secrecy — but does so in a manner that creates normative incoherence — cannot satisfy this standard.
Applied to the facts, these principles compelled a single conclusion: the legislative failure to harmonize the Banking Law with the amended KAS Act cannot be construed as an implicit expansion of the exceptions to banking secrecy. The bank was not only entitled to refuse disclosure — it was obligated to do so.
V. The Marginalia: Proportionality and Institutional Courtesy
The court appended a remark — formally obiter dictum but practically significant — concerning the conduct of the customs and fiscal office. It observed that the bank had not ignored the demand; rather, it had responded promptly, articulating specific legal concerns and requesting clarification. The office’s decision to impose a financial penalty without any attempt at dialogue was characterized as “somewhat premature and excessive” (nieco przedwczesna i nadmierna). This pattern of disproportionate administrative response represents a recurring concern in taxpayer protection against unlawful official conduct.
This observation carries implications beyond the immediate case. It signals judicial receptivity to arguments that revenue authorities must, before resorting to punitive measures, exhaust reasonable avenues of communication with regulated entities — particularly where those entities act from a position of legitimate caution, motivated by their own legal obligations.
VI. Broader Implications
A. For Taxpayers and Business Enterprises
The judgment establishes that the mere existence of a preliminary investigation in its in rem phase — without the formal presentation of charges — does not authorize revenue authorities to obtain unrestricted access to an individual’s banking records. This constitutes a meaningful procedural safeguard, operative at the stage when the person concerned may have no knowledge whatsoever of the pending investigation. It is worth noting that statutory time limits on the duration of regulatory inspections provide a complementary layer of protection against fiscal overreach.
For enterprises with cross-border operations, those maintaining foreign bank accounts, or those subject to international tax information exchange regimes, the ruling underscores the importance of understanding the precise boundaries of administrative authority over financial data.
B. For the Banking Sector
The ruling reinforces the bank’s role as a fiduciary gatekeeper — not a passive instrument of state power. Banks possess both the right and the duty to verify whether an official demand formally satisfies the statutory prerequisites established by the Banking Law. While a bank may not investigate the substantive truth of the representations made in such a demand (for example, whether proceedings have in fact been commenced), it may and must ascertain whether the demand, on its face, invokes the requisite legal predicates.
C. For the Legislature
The court expressly identified the normative incoherence and called for legislative correction. The scholarly literature — notably Stolarski’s analysis in Prokuratura i Prawo (2023, No. 9) — confirms that the mechanism for obtaining banking information by KAS authorities “requires correction ensuring correlation between the content of Article 105(1)(2)(e) of the Banking Law and the wording of Article 48(1) of the KAS Act.” Until such correction occurs, the Banking Law’s substantive conditions define the outer boundary of permissible disclosure. Any competent tax advisory practice must account for this structural gap in counseling clients on the scope of fiscal authority access to financial records.
VII. Conclusion
The WSA in Opole’s judgment in Case I SA/Op 328/23 is a carefully reasoned intervention in one of the more consequential normative collisions in contemporary Polish fiscal law. Its central holding — that the Banking Law’s provisions on banking secrecy constitute lex specialis vis-à-vis the KAS Act’s general competence provisions, and that the legislature’s failure to harmonize the two statutes cannot be construed to the detriment of privacy rights — rests on a foundation of constitutional principle, collision theory, and the doctrinal architecture of banking confidentiality.
The practical import is straightforward: revenue authorities may not, in the current legal landscape, compel banking disclosure during the in rem phase of fiscal criminal investigations. The bank’s refusal to comply with an insufficiently predicated demand does not constitute a sanctionable offense. And where the normative terrain is uncertain, the constitutional commitment to privacy — understood as a principle of both domestic and European law — resolves the uncertainty in favor of the individual.
One may reasonably anticipate that this reasoning will be tested before the Supreme Administrative Court. Whether the legislature will intervene before that occurs remains to be seen. What is clear, however, is that the WSA in Opole has articulated a principled framework that places the burden of legislative coherence precisely where it belongs: on the state, not on the institutions charged with safeguarding the financial privacy of citizens.
Founder and Managing Partner of Skarbiec Law Firm, recognized by Dziennik Gazeta Prawna as one of the best tax advisory firms in Poland (2023, 2024). Legal advisor with 19 years of experience, serving Forbes-listed entrepreneurs and innovative start-ups. One of the most frequently quoted experts on commercial and tax law in the Polish media, regularly publishing in Rzeczpospolita, Gazeta Wyborcza, and Dziennik Gazeta Prawna. Author of the publication “AI Decoding Satoshi Nakamoto. Artificial Intelligence on the Trail of Bitcoin’s Creator” and co-author of the award-winning book “Bezpieczeństwo współczesnej firmy” (Security of a Modern Company). LinkedIn profile: 18 500 followers, 4 million views per year. Awards: 4-time winner of the European Medal, Golden Statuette of the Polish Business Leader, title of “International Tax Planning Law Firm of the Year in Poland.” He specializes in strategic legal consulting, tax planning, and crisis management for business.
