Cross-examining the Expert Witness by Dean Brett Part 1

In How to prepare to cross-examine an expert witness, attorney Dean Brett writes on what he describes as “one of the trial attorney’s most difficult tasks.”

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.

Why then ever cross-examine an expert witness? Only because you have no alternative.

If you bring a claim of professional negligence or products liability, you are claiming that the defendant made an error in his own field of expertise, and you thereby incur an obligation to your client to prove the standard of conduct in that field of expertise and to cross-examine expert witnesses called to defend on the basis that the standard is not as you allege, or if it is, that it was met.

To fail to cross-examine is to concede the heart of the claim. Even if you try only “simple” negligence claims, you must be prepared to meet witnesses with expertise in engineering, accident reconstruction, medicine, psychology, vocational rehabilitation, and economics, to name a few.

Precisely because they are so difficult to examine, your opponent will insist on presenting the testimony of experts on the critical issues of the case. Those experts, because they are looked up to by the jury and because they are often hired for the specific purpose of destroying a necessary element of your proof, often cause more damage than lay witnesses and thus compel cross-examination. Failure to examine expert witnesses may be viewed by the jury as a surrender on the critical issues they support.

The next installments of this article series will be:

The four main advantages the trial lawyer has against the expert witness defending his home territory;
The four stages of general preparation for cross-examination of a defense expert;
The three conceptual categories of potential lines of questioning;
Final preparation for the cross-examination;
The Ten Commandments of cross-examination, plus four more.
An example cross-examination of a defense economist.

Attorney Dean Brett has been practicing injury and wrongful death law for 40+ years. Learn more about Dean, his practice, and his cases at his biography page. To contact the Brett Murphy attorneys with questions about a potential claim, please call 1-800-925-1875 or complete our simple contact form.