A Warsaw-based technology company is locked in a construction dispute over a failed server room installation. The opposing party submits a court-appointed expert report that systematically undervalues the defects. The company's lawyers have 14 days to respond – and no specialist of their own lined up. That window closes fast, and a missed objection can be treated as acceptance of the expert's conclusions.
Expert witnesses in Polish court proceedings are regulated under the Kodeks postępowania cywilnego (Code of Civil Procedure, KPC) and the Kodeks postępowania karnego (Code of Criminal Procedure, KPK), depending on the case type. A court-appointed expert (biegły sądowy) is drawn from official registers maintained by district court presidents. The expert's written opinion becomes part of the evidentiary record, and challenging it requires a formal procedural response within a court-set deadline – typically 14 days.
This guide covers the full lifecycle: how experts are appointed, how opinions are challenged, what private expert opinions can and cannot do, and where the most consequential mistakes occur. Three business scenarios – manufacturing, IT services, and a foreign investor – illustrate the key decision points. Whether you are facing litigation Warsaw-side or managing cross-border exposure, the procedural mechanics here determine how much weight the court places on technical evidence.
How are expert witnesses appointed in Polish civil proceedings?
The appointment process begins when the court decides that resolving a factual question requires specialist knowledge. Either party may request an expert opinion, or the court may order one on its own motion. The expert is selected from the official register of court experts (lista biegłych sądowych), maintained by each District Court (Sąd Okręgowy) president. Registration requires documented qualifications and professional experience – typically at least five years in the relevant field.
Once appointed, the expert receives a formal written order specifying the questions to be answered. The timeframe for delivering the opinion is set by the court – commonly between 30 and 90 days, though complex technical matters often stretch to six months or more. The parties receive a copy of the appointment order and may submit written questions or objections to the scope within the deadline the court sets.
Costs follow a specific tariff. Expert fees in civil proceedings are calculated under the regulation on expert remuneration, based on an hourly rate multiplied by estimated complexity. A standard construction or accounting opinion can cost between PLN 3,000 and PLN 20,000; forensic IT analyses or medical opinions in damages cases can exceed PLN 50,000. The party requesting the opinion advances the fee. If that party wins, costs are recoverable.
- Check whether the proposed expert appears on the relevant District Court register before proceedings begin.
- Submit written questions to the court promptly – late additions to the expert's remit are routinely rejected.
- Verify the expert's declared specialisation matches the technical question at issue.
- Identify conflicts of interest early: an expert who previously advised the opposing party can be recused.
- Reserve budget for a supplementary opinion if the first one is incomplete.
The National Court Register (KRS) and court databases are publicly searchable, which allows parties to verify an expert's professional background independently. The Polish Financial Supervision Authority (KNF) maintains separate registers for financial experts used in regulatory proceedings. In arbitration Poland contexts, parties may agree to appoint experts outside the court register entirely – a flexibility that civil courts do not offer.
What happens after the expert delivers an opinion?
Delivery of the written opinion triggers a strict procedural clock. Each party has the court-set deadline – almost always 14 days – to submit written objections. Silence during this window is dangerous. Courts have treated a failure to object as implicit acceptance of the expert's methodology and conclusions. That outcome is difficult to reverse on appeal.
Objections must be substantive. A complaint that the expert "reached the wrong result" without identifying the specific methodological error carries little weight. Effective objections point to: factual assumptions the expert made without evidentiary support; a methodology inconsistent with current professional standards; failure to answer one of the court-ordered questions; or a conflict of interest not disclosed at appointment. Each ground should be supported by reference to the record or by attaching a private specialist's note.
We secured a favourable supplementary opinion in a manufacturing dispute for a client in the Silesia region (autumn 2025). The original court-appointed expert had applied an outdated depreciation method, reducing the assessed loss by over PLN 4m. Our written objections identified the specific professional standard violated, and the court ordered a second expert. The revised figure restored the full claim value.
If objections are filed, the court has three options. It may ask the same expert to clarify or supplement the opinion. It may call the expert to a hearing for oral cross-examination – a right any party may request and courts increasingly grant in high-value disputes. Or it may appoint a different expert entirely. The last option is the hardest to obtain; courts are reluctant to multiply expert costs without a clear methodological flaw in the first opinion.
When does a private expert opinion change the outcome?
A private expert opinion (opinia prywatna) is not treated as expert evidence under the KPC. The court classifies it as a party's own submission – essentially an extended factual argument. That distinction matters enormously. A private opinion cannot substitute for a court-appointed expert's findings. But it can shift the proceeding in two concrete ways.
First, a well-structured private opinion gives the court a technical framework for evaluating the court expert's methodology. Judges are not specialists. When a private opinion explains why a particular calculation method is wrong and cites the relevant professional standard, it equips the judge to ask the right questions during oral examination of the court expert. Second, a private opinion can demonstrate that the factual question is genuinely contested – which supports a request for a second court-appointed expert.
For a dispute lawyer advising a foreign investor, the private opinion also serves an internal function: it translates the court expert's technical findings into commercial terms that the client's board can evaluate. That translation is often missing, and clients make settlement decisions based on a misreading of what the court expert actually said.
The cost of a credible private opinion from a recognised specialist ranges from PLN 5,000 to PLN 30,000 depending on complexity. That expenditure is not recoverable as a litigation cost, even if you win. Factor it into the dispute budget from the outset. In KIO appeal proceedings before the National Appeals Chamber (Krajowa Izba Odwoławcza, KIO), private technical opinions play a larger role because KIO timelines are compressed – hearings typically conclude within 15 days of filing.
How should foreign investors approach expert evidence in Poland?
For a German investor entering a Polish construction or acquisition dispute, the first surprise is usually the court's exclusive control over expert selection. Unlike international arbitration Poland proceedings – where parties negotiate the appointment of jointly agreed experts – Polish civil courts choose from their own registers. The investor has no right to nominate a preferred expert, only to challenge one already appointed.
Language is the second complication. Expert opinions are delivered in Polish. There is no statutory obligation for the court to arrange translation unless a party formally requests it and advances the cost. Foreign investors who rely on summaries provided by local counsel – rather than reviewing the full opinion – miss the methodological detail that drives objection strategy. Translation of a 60-page technical opinion can cost PLN 2,000 to PLN 5,000 and takes one to two weeks. Budget both.
Our team obtained interim protective measures for a German investor's subsidiary in Lower Silesia (spring 2026), preserving assets worth over EUR 3m pending an expert opinion on construction defects. The measures were granted because we filed before the opposing party could transfer the disputed assets. Timing the application to the expert appointment schedule was the deciding factor.
Sanctions compliance adds a layer for investors with cross-border supply chains. Where the underlying transaction involves a sanctioned counterparty, the expert's valuation of assets or damages may intersect with sanctions screening obligations for Polish companies. Courts do not automatically flag this; the party's counsel must raise it. Ignoring the overlap can produce an expert opinion that is technically sound but legally unusable.
Foreign investors acquiring Polish real estate face an additional consideration. Property valuation experts (rzeczoznawcy majątkowi) are licensed separately under Polish property law, not under the general court expert framework. Their opinions carry statutory weight in expropriation and planning proceedings. For context on property acquisition procedures, see buying property in Poland.
What are the most common mistakes in managing expert evidence?
Procedural passivity is the most expensive mistake. Parties who receive a court expert's opinion and respond only with a general denial – rather than a structured technical objection within the 14-day window – forfeit the opportunity to reopen the evidentiary record. The opinion becomes fixed. On appeal, the higher court reviews the lower court's assessment of the expert's opinion; it rarely substitutes its own technical view. A missed objection at first instance precludes meaningful review on appeal.
The second mistake is appointing a private expert whose credentials do not match the court expert's specialisation. If the court expert is a certified construction engineer and the private opinion comes from an architect without engineering registration, the court will discount the private opinion regardless of its analytical quality. Match specialisation precisely.
Third: failing to request oral examination. Parties have the right to request that the court expert appear at a hearing and answer questions. In disputes involving contested assumptions – valuation dates, market comparables, damage causation – oral examination often reveals gaps that the written opinion conceals. This right must be exercised formally, in writing, before the court closes the evidentiary stage.
Cyprus-registered companies operating in Poland through subsidiaries face an additional procedural exposure. Expert opinions in Polish proceedings are served at the Polish address of record. If that address is not monitored, the 14-day response deadline passes unnoticed. For dispute resolution structures relevant to Cyprus entities, see dispute resolution for Cyprus companies doing business in Poland. Structural oversight of service addresses is not a legal formality – it is an evidentiary risk management issue.
To receive an expert assessment of your expert evidence strategy in Polish proceedings, contact info@kordeckipartners.com.
Frequently asked questions
Q: Can a party replace a court-appointed expert they disagree with?
A: Replacement is possible but not straightforward. A party must file a formal recusal motion identifying a specific ground – conflict of interest, lack of required qualifications, or a prior relationship with the opposing party. General dissatisfaction with the expert's conclusions is not a valid ground. Courts grant recusal motions in a minority of cases. The more effective route is usually to challenge the opinion's methodology and request a supplementary or second opinion rather than seeking full replacement.
Q: How long does the expert opinion process typically take, and what does it cost?
A: In civil proceedings, the full cycle from appointment to final opinion commonly takes three to nine months. Complex financial or medical disputes can extend beyond twelve months if supplementary opinions are ordered. Court expert fees range from PLN 3,000 for straightforward accounting reviews to over PLN 50,000 for multi-disciplinary forensic analyses. The advancing party pays upfront; the losing party bears the cost at judgment. Private opinions are not recoverable as litigation costs regardless of outcome.
Q: Is an expert opinion from foreign proceedings admissible in Polish courts?
A: A foreign expert opinion can be submitted as a document, but it does not carry the same evidentiary status as a Polish court-appointed expert's report. The court classifies it similarly to a private opinion – as a party's submission rather than independent expert evidence. To give foreign technical findings full evidentiary weight, the findings typically need to be reviewed and confirmed by a Polish court-appointed expert. This is a common misconception for international clients who assume that a well-regarded foreign expert's report will be treated as authoritative.
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 and dispute resolution. We work with Polish entrepreneurs, foreign investors, and in-house legal teams navigating expert evidence, arbitration Poland proceedings, and cross-border disputes. 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.