Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Cross Examination of Expert Witnesses


Published on

Enjoy the content.

Published in: Law
  • Be the first to comment

Cross Examination of Expert Witnesses

  1. 1. Cross-Examination of Expert Witnesses Michael DeBlis III, Esq.
  2. 2. Rule 702. Testimony by Experts • If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise, if (1) the testimony is based upon sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case
  3. 3. FRYE and DAUBERT tests
  4. 4. The “Sniffer” Machine • Dr. Vass and his laboratory stand to make a fortune selling their contraption of a smell machine to law enforcement across the country. If this judge allows it in the case, many people including Dr. Vass stand to make a lot of money. Never before has a judge allowed it, but these people know that they have a damn good chance with this particular judge allowing this machine to be used in trial. Once Vass’s machine is used in trial, it validates and elevates the value of Vass’s invention. He and the lab can then sell it to every police department in the nation. When that happens, they are off to the races with the U.S. Patent Office with Dr. Vass’s machine.
  5. 5. What does all this mean to us in a courtroom? • Expansion of pre-trial motions • Expansion of voir dire of experts • Real investigation of the science and the scientist
  6. 6. Challenging the expert • Either as to his or her credentials • The "expertise" itself • Use MOTIONS – You might not be able to keep out the testimony, but you may be able to limit it
  7. 7. Don’t ignore investigating and challenging the expert • Challenging the credentials • Three types of experts – Highly trained – On-the-job – Dubious training/dubious area
  8. 8. Strategy Considerations
  9. 9. Preparation of expert cross • Learn something about the area – Inbau & Moensens, Scientific Evidence in Criminal Cases • Use the phone • Get TRANSCRIPTS • Research – College texts – Read everything their expert has written
  10. 10. Interview the Expert Yourself
  11. 11. Experts and Language • Learn theirs • Learn to translate for jury • Don't patronize
  12. 12. Basic Principles • Normal principles of cross apply • Extensive preparation essential • Only ask leading questions • One fact per question • Never ask a question to which you do not know the answer • Develop a system with that you are comfortable with
  13. 13. Special Problems When Witness Is an Expert • Witness is an expert in the field – you are not • Witness is more difficult to control than a lay witness • Witness is likely well-educated and articulate • Witness is experienced at courtroom testimony
  14. 14. Examples of Cross-Examination of Experts • Forensic Pathologist in State v. Morehead • Radiologist in State v. Carey • Shaken baby syndrome experts in State v. Carey
  15. 15. Forensic Pathologist • State v. Morehead (client accused of strangling grandmother) – Defense was that grandmother died of heart failure – Cross-examination of medical examiner was critical to outcome – Examples of controlling the witness and learning the terminology
  16. 16. Experts on the Shaken Baby Syndrome • State v. Carey (client accused of shaking 5- month old baby causing brain damage) – Multiple expert witnesses for the state – Cross of radiologist who reviewed CAT scan and MRI – Cross of non-treating outside expert on Shaken Baby Syndrome
  17. 17. Cross-Examination • What should jury feel about witness when you are done? – Is this good science? – Can they trust the witness? – Can they trust the evidence? – Can they rely on the evidence?
  18. 18. Examine Bias • Who do they testify for? • Follow the money • Membership in groups • Built-in personal bias
  19. 19. Challenging the result • Things not done cross • Result is not OBJECTIVE • Levels of certainty
  20. 20. Use demonstrative aids
  21. 21. Cross by learned treatise
  22. 22. The Ten Principles of Preparation for Cross of an Expert • (1) Identify opinions that have to be challenged • (2) Assemble all materials needed for cross- examination • (3) Obtain complete CV of opposing expert • (4) Research expert’s prior testimony • (5) Investigate allegations of mistake or misconduct
  23. 23. The Ten Principles of Preparation for Cross of an Expert • (6) Research treatises and articles pertinent to the subject matter • (7) Retain an expert • (8) Meet with opposing expert before trial • (9) Learn the pertinent terminology in the subject matter • (10) Develop a system to organize your cross- examination