A Warsaw-based technology company is mid-way through commercial litigation when the opposing party challenges the methodology of the court-appointed expert. The hearing is adjourned. Months pass. The case stalls – and with it, the client's ability to enforce a contract worth several million zloty. This scenario plays out regularly before Polish district and regional courts, and it is entirely avoidable with the right preparation.
Expert witnesses in Polish court proceedings are appointed by the court from a register maintained by each regional court president, or selected as ad hoc specialists in narrower technical fields. The court sets a deadline – typically 30 to 90 days – for the expert to deliver a written opinion. Parties may then submit written objections, request a supplementary opinion, or move for a different expert to be appointed.
This alert covers the procedural framework governing expert evidence, the most common points of failure that delay or derail proceedings, and the immediate steps parties should take to protect their position. It is relevant to any business involved in commercial litigation, construction disputes, or cross-border enforcement proceedings before Polish courts.
How does the Polish expert witness system work?
Polish civil procedure distinguishes between two categories of expert. The first is the registered court expert (biegły sądowy), listed on registers held by the presidents of regional courts (sądy okręgowe) across Poland. The second is the ad hoc specialist (specjalista), appointed for a single case when no registered expert covers the relevant field. Both categories are subject to supervision by the National Council of the Judiciary (Krajowa Rada Sądownictwa, KRS) and the Ministry of Justice.
The court appoints the expert by formal ruling. The parties have no veto, but they may propose names and object to a specific appointment on grounds of conflict of interest or lack of qualifications. An objection must be filed promptly – delay forfeits the right to challenge. Once appointed, the expert receives case files and a list of questions formulated by the court, sometimes with input from the parties.
Fees are regulated. For standard opinions, the court sets remuneration within a statutory band. Complex technical opinions – in construction, environmental, or financial matters – can reach PLN 15,000 or more per assignment. The losing party typically bears the cost, but the court may apportion fees differently in partial-win situations.
- Registered experts: listed per regional court, renewable every 5 years
- Ad hoc specialists: appointed case-by-case, no registration requirement
- Deadline for opinion: set by court, usually 30–90 days from file receipt
- Objection window: 14 days from service of the written opinion
- Cost liability: follows the judgment on costs
Foreign parties should note that the National Court Register (Krajowy Rejestr Sądowy, KRS) and the Polish Financial Supervision Authority (Komisja Nadzoru Finansowego, KNF) are frequently referenced in financial and corporate disputes where expert evidence on valuation or regulatory compliance is required. Understanding which institution's records an expert will draw on matters for scoping the opinion correctly from the outset.
What are the most critical failure points – and what should you do now?
The single greatest source of delay is an inadequately scoped set of questions submitted to the expert. If the court's questions are too broad, the expert produces a sprawling opinion that neither party can effectively challenge. If too narrow, the opinion misses the central issue and a supplementary opinion – adding another 60 to 120 days – becomes inevitable. Parties have a right to propose questions before the expert is instructed; failing to exercise that right is a strategic error that precludes correction later.
We secured a reversal of an unfavourable expert opinion in a construction dispute for a developer client in the Małopolska region (autumn 2025). The original opinion had been based on outdated cost indices. By filing a detailed written objection within the 14-day window and requesting a supplementary opinion, we obtained a revised valuation that reduced the claimed damages by over PLN 3.2m.
A second failure point is passive acceptance of the appointed expert. Parties in cross-border proceedings often assume the court's choice is final. It is not. A party may apply to replace the expert on grounds of bias, prior involvement, or demonstrable lack of specialist knowledge. This application must be supported by evidence – a bare assertion will be dismissed. The window to act is short: once the expert has delivered the opinion, replacement becomes procedurally much harder.
For matters touching tax disputes or sanctions compliance, expert evidence on accounting standards or transfer pricing methodology is increasingly decisive. An expert who applies the wrong benchmark can shift the outcome by millions of zloty. Engaging a technical advisor to shadow the court-appointed expert – reviewing methodology before the formal opinion is issued – is a legitimate and effective safeguard.
Immediate action items for parties currently in proceedings:
- Review the court's list of questions before the expert is instructed – submit proposed additions in writing
- Verify the appointed expert's registration status and any prior involvement with the opposing party
- Calendar the 14-day objection deadline from the date of service of the opinion
- Instruct a technical shadow advisor for opinions involving financial modelling or construction costs
In arbitration Poland proceedings under institutional rules, the parties have considerably more control over expert selection. If your dispute involves a contractual arbitration clause, the procedural flexibility available at bodies such as the Court of Arbitration at the Polish Chamber of Commerce (Sąd Arbitrażowy przy Krajowej Izbie Gospodarczej) may make arbitration the preferable forum precisely because of this. A dispute lawyer advising at the contract stage can build that optionality in from the start.
One further point on KIO appeal proceedings – procurement disputes before the National Appeals Chamber (Krajowa Izba Odwoławcza, KIO) – expert evidence is handled under accelerated timelines. The KIO must issue its ruling within 15 days of the appeal being filed. Expert input in KIO proceedings is therefore compressed and must be prepared in advance, not assembled reactively.
Your specific situation carries consequences that cannot be reversed once the expert's opinion is admitted into the record. A flawed opinion, unchallenged within the statutory window, becomes part of the evidentiary foundation of the judgment. To receive an expert assessment of your position in ongoing or anticipated proceedings, contact info@kordeckipartners.com.
Frequently asked questions
Q: Can a party in Polish litigation appoint its own expert?
A: A party may commission a private expert opinion (opinia prywatna) and submit it as a document in the proceedings. However, Polish courts treat private opinions as party submissions, not as independent expert evidence. The court-appointed expert's opinion carries significantly greater evidentiary weight. A private opinion is most effective when used to formulate objections to the court-appointed expert's methodology, not as a standalone substitute.
Q: How long does the expert evidence phase typically add to proceedings?
A: In straightforward commercial cases, a single expert opinion adds 3 to 6 months. Where a supplementary opinion is ordered – or where the expert is replaced – the delay extends to 9 to 18 months. Construction and environmental disputes routinely involve multiple experts across different disciplines, making the expert phase the longest single element of first-instance proceedings. Factoring this into litigation budgets and settlement timing is essential.
Q: Is it true that courts always follow the expert's opinion?
A: This is a common misconception. Courts are not bound by expert opinions. A judge may depart from an expert's conclusions if the opinion is internally inconsistent, rests on factual assumptions not supported by the evidence, or conflicts with other admitted evidence. In practice, however, departing from an unchallenged expert opinion is rare. The practical lesson is that the objection stage – not the final hearing – is where the expert's opinion is most effectively contested.
KORDECKI & Partners is a law firm based in Warsaw and Krakow, advising business clients across 30 jurisdictions. Our team combines expertise in Polish and international law with a practical approach to commercial litigation, arbitration, and dispute resolution. We work with Polish entrepreneurs, foreign investors, and in-house legal teams. To discuss your situation, contact info@kordeckipartners.com.
Disclaimer: This publication is provided for informational purposes only and does not constitute legal advice. The information herein should not be relied upon as a substitute for professional legal counsel tailored to your specific circumstances. KORDECKI & Partners assumes no liability for actions taken or not taken based on the contents of this material. For advice regarding your particular situation, please contact info@kordeckipartners.com.