Guiding Principles for Expert Witnesses and Standards to be Followed in Expert Reports

Under Article 6 of Law No. 6754, the Expert Witness Department has determined the "Guiding Principles for Expert Witnesses and Standards to be Followed in Expert Reports."

The regulation aims to increase the awareness and effectiveness of expert witnesses in their activities, and to establish minimum standards for expert reports applicable nationwide, ensuring uniform practice in this field.

1. An expert witness must have very good knowledge and skills in their assigned field. Therefore, when applying for registration on the expert witness list, they should pay special attention to the selection of the primary and sub-specialty areas.

2. If, after preliminary examination, the expert determines that the matter does not fall within their expertise, they must notify the appointing authority within one week and should not accept the assignment.

3. If the expert has doubts regarding the scope of their duties, they must request written clarification from the appointing authority and perform their examination according to the written instructions provided.

4. The expert must request from the appointing authority that the assignment be made in accordance with the legislation, including the scope and the questions to be answered.

5. The expert must accept assignments from all provinces and districts within the jurisdiction of the expert witness regional board they are registered with, unless there is a valid excuse. Avoiding an assignment may lead to removal from the registry or list.

6. When it is possible to examine the file via UYAP, the expert should request access to review the file digitally to minimize time and effort instead of requiring physical submission.

7. The expert must prepare the report carefully and diligently, responding to all questions, with the awareness that their evaluation assists the judge in ensuring justice.

8. If the expert needs the knowledge of another specialist to clarify or determine an issue, they should request the appointing authority to assign an expert in that field and benefit from their knowledge.

9. The expert should not make findings or express opinions on matters outside their expertise that are not directly relevant to the dispute. Their task is to analyze the provided data within their specialty.

10. An expert’s scope is generally limited to their knowledge and the questions asked. They cannot comment on claims or defenses, even if the appointing authority requests it. Evaluating claims and defenses is the responsibility of the appointing authority.

11. When preparing a report, the expert may consult the parties for information if necessary and with the appointing authority's approval, submitting their request in writing. However, one party cannot be heard without the other, even if approved.

12. If contacted by a party, representative, or third party, the expert should avoid providing information and immediately inform the appointing authority.

13. The expert must base their report on concrete, specific reasons in accordance with scientific data. The report should also include justifications suitable for review by appellate and cassation courts.

14. If measurements are required, the expert must perform them personally and not rely on measurements provided by the parties, explaining units and criteria in the report.

15. The expert should not provide discretionary evaluations; after presenting the facts clearly, interpretation and judgment are left to the judge.

16. Determining the need for technical knowledge is a judicial task; the expert cannot make legal evaluations. If in doubt, the expert should consult the appointing authority.

17. Without technical or specialized knowledge, the expert cannot assess evidence to form opinions. However, evidence can be used as support for technical evaluations.

18. The report should be clear, legible, and understandable, using Turkish equivalents of technical terms where possible.

19. If requested, the expert must evaluate previously submitted expert opinions in terms of technical knowledge and discuss them in the report.

20. The expert must reflect all examined documents (ledger, receipts, invoices, notes, etc.) in the report for judicial review.

21. The expert may request missing materials necessary for the report from the appointing authority.

22. The report should be concise, clear, and focused, avoiding unnecessary details that may obscure findings.

23. If the subject is long or involves multiple issues, the report should be divided into paragraphs and headings to prevent contradictions and enhance readability.

24. The report must strictly address the assigned questions and demonstrate the scientific basis for each answer.

25. If a site inspection is required, the expert should request sufficient time to review the file beforehand and note any missing documents or information needed for the inspection.

26. For site inspections, the expert should provide information on the location, coordinates, terrain, weather, and transportation, and carry necessary equipment (GPS, CORS, etc.) during the inspection.

27. Determining fault is the judge’s authority; the expert cannot evaluate fault percentages or responsibility levels.

28. If unable to submit the report on time, the expert must request an extension, explaining the reason.

29. If assigned to resolve contradictions in previous reports, the expert must justify which findings they agree with or present a different evaluation.

30. Additional reports must address the reason for the assignment and provide a definitive solution.

31. The expert must explain the rationale for conclusions based on technical knowledge to facilitate review and prevent arbitrary interpretations.

32. When assigned as part of a panel, experts must deliberate collectively. Minority opinions should be indicated, and separate reports may be submitted if necessary.