INTERNATIONAL STANDARDS OF PROFESSIONAL ETHICS FOR FORENSIC EXPERTS AND THEIR ROLE IN PREVENTING EXPERT ERRORS: A COMPARATIVE LEGAL ANALYSIS
DOI:
https://doi.org/10.32782/forensic.science.2026.3.2Keywords:
expert impartiality, cognitive bias, quality of evidence, forensic examination, procedural objectivity, interpretation errorsAbstract
This research project aims to determine, through a comparison of the legal systems of Ukraine, Germany, and Poland, whether there is a relationship between the application of international ethical standards and the types of expert errors committed during forensic medical examinations. This objective is achieved through a comparative legal empirical analysis using publicly available court decisions covering the five-year period from 2020 to 2025. The empirical sample consists of 30 individual court cases in which 47 instances of expert error were identified. Since a single expert opinion may contain more than one identified error, the total number of recorded error instances exceeds 47. Cognitive errors accounted for 51.1% of all identified errors in the empirical sample, while methodological errors represented 29.8% and ethical errors 19.1%. The assessment of compliance with ethical principles revealed that 38.3% of all cases demonstrated full compliance, 34.0% showed partial compliance, and 27.7% involved violations of ethical standards. A country-bycountry analysis indicated that Ukraine recorded the highest number of violations (23), followed by Poland (14) and Germany (10), suggesting that different jurisdictions apply ethical standards with varying degrees of consistency. Statistical analysis demonstrated a statistically significant correlation between the level of compliance with ethical standards and the number of identified erroneous expert conclusions. The findings indicate that even where ethical standards are formally observed, erroneous expert conclusions may still arise due to cognitive and procedural factors. This study has the potential to contribute to quality assurance mechanisms in forensic medical examinations and to support the effective implementation of ethical standards in professional practice.
References
1. Alafer F. Emerging imaging technologies in forensic medicine: A systematic review of innovations, ethical challenges, and future directions. Diagnostics. 2025. Vol. 15, No. 11. P. 1410.
2. Alfaro C. R., Ureña Mora D., Chacón Hernández M., Quigley-McBride A. A practical approach to mitigating cognitive bias effects in forensic casework. Forensic Science International: Synergy. 2024. Vol. 10. P. 100569.
3. Barros F., Kuhnen B., Serra M. C., Fernandes C. M. S. Forensic sciences: Ethical principles and biases. Revista Bioética. 2021. Vol. 29, No. 1. P. 55–65.
4. Biedermann A., Bozza S., Taroni F. Quality management in forensic science: A closer inspection. Forensic Science International. 2023. Vol. 343. P. 111550.
5. Bondarenko-Berehovych V. Strategies for minimizing errors in forensic expert practice. Theory and Practice of Forensic Science and Criminalistics. 2024. Vol. 37, No. 4. P. 29–38.
6. Cain C. F., Smith O. K. H. The impact of expert witness knowledge on perceived credibility: Implications for not guilty by reason of insanity (NGRI) endorsement. Behavioral Sciences. 2025. Vol. 15, No. 10. P. 1411.
7. Coltri M. A., Uys W. R., Joubert K. Investing AI ethics in forensic investigations: Development, policies, and best practices. Athens Journal of Business & Economics. 2025. Vol. 11, No. 4. P. 355–376.
8. Council of Europe. Guidelines on the role of court-appointed experts in judicial proceedings. 2016. URL: https://rm.coe.int/168074827a.
9. Council of Europe. CEPEJ report on judicial experts. 2021. URL: https://rm.coe.int/cepej-report-on-judicial-experts/1680a4b1f3.
10. Council of Europe. Guide on Article 6 of the European Convention on Human Rights (criminal limb). 2022. URL: https://icct.nl/sites/default/files/import/publication/guide_art_6_criminal_eng.pdf.
11. Cuellar M. The prosecutor’s fallacy and expert testimony: A modern take using likelihood ratios. arXiv. 2025. URL: https://doi.org/10.48550/arXiv.2502.03217.
12. Dinis-Oliveira R. J. Forensic science or sciences? The recognition as an independent science and redefinition of expert practices based on transdisciplinary. Forensic Sciences Research. 2025. Vol. 10, No. 3. P. owaf012.
13. Dror I. E. Cognitive and human factors in expert decision making: Six fallacies and the eight sources of bias. Analytical Chemistry. 2020. Vol. 92, No. 12. P. 7998–8004.
14. Dror I. E., Kukucka J. Linear sequential unmasking–expanded (LSU-E): A general approach for improving decision making as well as minimizing noise and bias. Forensic Science International: Synergy. 2021. Vol. 3. P. 100161.
15. Dror I. E., Pierce M. L. ISO standards addressing issues of bias and impartiality in forensic work. Forensic Science International. 2019. Vol. 302. P. 109903.
16. Du M. Analysis of errors in forensic science. Journal of Forensic Science and Medicine. 2017. Vol. 3, No. 3. P. 139–143.
17. European Court of Human Rights. Doorson v. the Netherlands (Application no. 20524/92). 1996. URL: https://hudoc.echr.coe.int/eng?i=001-57972.
18. European Network of Forensic Science Institutes. Code of conduct. 2005. URL: https://enfsi.eu/wp-content/uploads/2016/09/code_of_conduct.pdf.
19. European Network of Forensic Science Institutes. Guideline for evaluative reporting in forensic science. 2015. URL: https://enfsi.eu/wp-content/uploads/2016/09/m1_guideline.pdf.
20. Federal Ministry of Justice. German Code of Criminal Procedure (Strafprozessordnung – StPO). 1987. URL: https://www.gesetze-im-internet.de/englisch_stpo/.
21. Hefetz I. Evaluating bias in forensic evidence: From expert analysis to AI-based decision tools. Forensic Science International: Synergy. 2025. Vol. 11. P. 100645.
22. International Organization for Standardization. ISO/IEC 17020:2012 – Conformity assessment – Requirements for the operation of various types of bodies performing inspection. 2012. URL: https://www.iso.org/standard/52994.html.
23. International Organization for Standardization. ISO/IEC 17025:2017 – General requirements for the competence of testing and calibration laboratories. 2017. URL: https://www.iso.org/standard/66912.html.
24. Lund S. P., Iyer H. The influence of validation data on logical and scientific interpretations of forensic expert opinions. arXiv. 2024. URL: https://doi.org/10.48550/arXiv.2403.02663.
25. Madureira-Carvalho Á., Gomes N. G. M., Dias-da-Silva D., Azevedo R. M. S., Fernandes L. M., Dinis-Oliveira R. J., Caldas I. M. The code of ethics and conduct for forensic specialists: A framework from the Portuguese Association of Forensic Sciences. Forensic Sciences. 2023. Vol. 3, No. 1. P. 169–178.
26. Martynenko N. Establishing a system of professional self-government of forensic scientists in Ukraine. Forensic Science International: Reports. 2025. Vol. 11. P. 100412.
27. Martynenko N. Methodological support for forensic science in the USA and Ukraine: A comparative study. Forensic Science International: Synergy. 2025. Vol. 10. P. 100571.
28. National Research Council. Strengthening forensic science in the United States: A path forward. National Academies Press. 2009. URL: https://www.nap.edu/catalog/12589/strengthening-forensic-science-inthe-united-states-a-path-forward.
29. Otgaar H., De Beuf T. L. F., Sauerland M., Schincariol A. Evaluating the validity of testimony: The role of the order of evidence. Forensic Science International: Synergy. 2024. Vol. 9. P. 100562.
30. Polish Parliament. Polish Code of Criminal Procedure. 1997. URL: https://isap.sejm.gov.pl/isap.nsf/DocDetails.xsp?id=WDU19970890555.
31. Pratap C. E. Ethical aspects of forensic expert evidence in criminal cases. International Journal of Novel Research and Development. 2022. Vol. 7, No. 3. P. 746–751.
32. President’s Council of Advisors on Science and Technology. Forensic science in criminal courts: Ensuring scientific validity of feature-comparison methods. Executive Office of the President of the United States. 2016. URL: https://obamawhitehouse.archives.gov/sites/default/files/microsites/ostp/PCAST/pcast_forensic_science_report_final.pdf.
33. San Pietro D., Tagliaro F., Adamowicz M. S. A preliminary assessment of the effect of PreCR™ DNA repair treatment on mixture ratios in two person mixtures. Science & Justice. 2018. Vol. 58, No. 5. P. 308–314.
34. Verkhovna Rada of Ukraine. Law of Ukraine “On Forensic Examination” No. 4038-XII. 1994. URL: https://zakon.rada.gov.ua/laws/show/4038-12.
35. Vredeveldt A., van Rosmalen E. A. J., van Koppen P. J., Dror I. E., Otgaar H. Legal psychologists as experts: Guidelines for minimizing bias. Psychology, Crime & Law. 2024. Vol. 30, No. 7. P. 705–729.
36. Vuille J., Lupária L., Taroni F. Scientific evidence and the right to a fair trial under Article 6 ECHR. Law, Probability and Risk. 2017. Vol. 16, No. 1. P. 55–68.
37. Wahlberg L., Dahlman C. The role of the expert witness. Philosophical Foundations of Evidence Law / ed. by C. Dahlman, A. Stein, G. Tuzet. Oxford University Press, 2021. URL: https://doi.org/10.2139/ssrn.3758820.
38. Ward T. The forensic ethics of scientific communication. The Journal of Criminal Law. 2023. Vol. 87, No. 1. P. 3–17.
39. Yadav P. K. Ethical issues across different fields of forensic science. Egyptian Journal of Forensic Sciences. 2017. Vol. 7, No. 1. P. 10.
