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Law 101: Legal Guide for the Forensic Expert

Additional Tips for the Novice or Experienced Expert

Additional Tips for the Novice or Experienced Expert
National Institute of Justice (NIJ) (see reuse policy).
  1. Don't be afraid to ask for clarification of unclear questions.
  2. Make sure the expert's testimony is consistent with experience and the technical literature.
  3. Explain in layman's terms how tests and measurements were performed.
  4. Make and maintain eye contact with the examining attorney. This helps to establish credibility.
  5. Be certain of the meaning of definitions used in questions and answers.
  6. Do not be too brief when giving answers to questions.
  7. Use examples for points of comparison.
  8. Limit the use of examples to one good one for each major point.
  9. Demonstrative materials require close attention of the trier of fact. Keep them simple.
  10. Confirm the use of demonstrative materials with counsel and the opposition.
  11. Step to one side of illustrations — face the audience.
  12. Draw first and then turn toward the audience.
  13. Be sure to make demonstrative drawings VERY LARGE.
  14. Do not try to read and talk at the same time.
  15. Do not look through the case file and talk at the same time.
  16. Meet with the attorney before the trial to discuss testimony.
  17. Translate statistics into a form that is meaningful for the case.
  18. Have a strong recollection of the facts in the case file.
  19. Generally stand firm on your testimony position.
  20. Admit errors at once.
  21. Be very familiar with your own résumé or curriculum vitae.
  22. Do not cut off questions or answer too quickly. Pause to take a breath.
  23. Know the relevant technical literature — particularly "the bible" in the expert's field of expertise — as well as the prominent journals.
  24. Ask the retaining attorney what items to take to court or deposition.
  25. Raise and lower the tone of voice and volume for effect.
  26. Use the "pregnant pause" as an effective response technique for conveying persuasive findings and opinion with confidence.
  27. Fix your eyes on the recipient of the information.
  28. Remember that court business is always very serious business.
  29. Know that it is permissible to laugh at obvious humor — but never be a joker.
  30. Refer to notes and notebooks during testimony as needed because they are helpful.
  31. Know that your notes and notebook can and will be looked at by the opposition.
  32. Let the examiner finish the question before starting to answer.
  33. Avoid putting your hands near your face — this signals nervousness and insecurity.
  34. Be sure that the preservation of chain of custody and evidence are perfect.

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