Throughout my years as a trial attorney, I have found that one of the most challenging aspects of trial is cross-examining an expert witness. I’ve written an article series describing my experience and the methods I’ve used that have allowed me to gain real advantages through cross-examination of an expert witness. These methods have proven highly successful for me for 40+ years. I will be publishing the article series over the next several days, so keep an eye out for the next installment.
Part 1 - Why cross-examine an expert witness?
The cross-examination of an expert witness is one of the trial lawyer’s most difficult tasks. The expert must be assumed to be an intelligent person who has focused his intelligence on the particular scientific, technical, or specialized field of inquiry. The rules of evidence allow the expert witness certain unique advantages, including:
the chance to state his opinion (ER 702);
to include conclusions on the ultimate fact to be decided by the jury (ER 704);
to be buttressed by facts or data not in evidence (if of a type reasonably relied upon by other experts in the particular subject matter) (ER 703);
to include facts even if those facts or data would not otherwise be admissible in evidence (ER 703);
to include facts or data which the expert need not disclose in direct examination (ER 705);
allowing the jury to be told the expert was appointed not by your opponent, but by the court (ER 706).
To make matters even more challenging, frequently the expert witness has more courtroom experience and savvy than the cross examiner.
“As a general thing, it is unwise for the cross-examiner to attempt to cope with a specialist in his own field of inquiry. Lengthy cross-examination along lines of the expert’s theory is easily disastrous and should rarely be attempted.” Francis Wellman, The Art of Cross-Examination, 1903.