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At Your Defense

Tips for Being an Effective Expert Witness

Reyes, Carlo MD, JD

doi: 10.1097/01.EEM.0000586488.57901.7e
At Your Defense



Being a medical expert witness can be exciting, financially rewarding, and intellectually stimulating. Applying your specialty training to the art of expert witness testimony seems like a low-risk, high-reward scenario. If you are ready to become a legal advocate, it's important to recognize that this is a new skillset that requires your earnest effort to learn.

The attributes of a good expert witness: A qualified expert witness generally needs to be actively practicing in the medical field relevant to the case. It would not be proper for an expert witness to testify to the standard of care for a type of medicine he rarely encounters. An EP who has been practicing exclusively in urgent care for 10 years may not be a good expert to testify on the emergent management of multisystem traumas.

Once an expert witness is deemed qualified, the pressing question is whether he can effectively convince a jury about the medical standard of care. A good expert witness needs to be convincing and trustworthy, and to be convincing, he must possess the requisite knowledge, training, and experience; demonstrate integrity and honesty; and speak eloquently and respond calmly during cross-examination.

Demonstrating training and experience is as simple as reciting one's years in training and current clinical practice, but responding calmly to a cross-examiner's barrage of questions is a particular skill not taught during medical training. Trial attorneys are specifically trained in cross-examination to make a witness flustered, state contradictory things, and look unprepared, unknowledgeable, disingenuous, or all three.

A few pointers can help you become a better expert witness. Public speaking is a critical skill. Presenting at grand rounds, medical conferences, and other medical teaching venues will improve your oratory skills and prepare you for speaking in the legal arena. Watching a good expert witness during cross-examination is the best way to understand the attributes needed.

How to survive cross-examination: Before answering, an expert witness must actually understand the question being asked. Listen carefully to an attorney's question before rushing to answer. It is OK to say you don't understand the question or to paraphrase the question to confirm understanding. Do this before answering. This slows the questioning, and allows mental preparation in answering sufficiently.

Do not readily agree with a cross-examiner's overly-generalized medical conclusions. It's important to know what to say when an attorney asks a leading question like, “Isn't it true that any responsible physician would have ordered a CT scan for a patient with severe headache?” A good expert would apply the particular facts in the case that makes it reasonable not to order the scan. A good expert answers questions with a high degree of accuracy (avoiding exaggerated statements) and specificity (answer only the question being asked). Another tactic used by attorneys is to get an expert to estimate when estimations are impossible. Don't offer an estimate if there is no valid one. Another example is when attorneys try to ask yes-or-no questions when the subject matter is far too complex and a yes-or-no answer would mislead the jury into believing something false.

Stay calm, cool, and collected during cross. This is a personality trait more than anything else. Some of us just can't be expert witnesses if we can't sit comfortably during cross. Your demeanor, ease of speaking, facial expressions, and body positioning may tip off opposing counsel (and the jury) that your opinion is not believable. The delivery of expert testimony during trial is one of the most important attributes, and that is why the most effective experts are the ones who can speak convincingly in front of a jury.

Medical-legal preparation means making sure that the expert fully understands the medical topics about which he is being asked to opine. Being well prepared means confirming the pathophysiology of a medical condition, and requires one to speak intelligently and concisely in a way that is simple for the jury to understand. This may include being able to recite medical references that support the description of a medical condition offered as an expert opinion. Preparation also involves reading all documents in the medical record, all depositions, and all reports made available to you. A valid medical expert opinion is one that is foundationally supported by accepted medical knowledge and accurately reflects the facts of the case.

Dogmatic positions should be avoided. It is better to be seen by a jury as an expert who is appropriately influenced by the facts of the case, not dogmatically married to a position that supports your side. A corollary to this is that prior expert-witness work for both plaintiffs and defendants tends to make an expert witness appear unbiased and trustworthy to the jury. Generally, the jury will see an expert as rational and trustworthy when he appears relaxed and unbiased.

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Dr. Reyesis the vice chief of staff and the assistant medical director of emergency medicine at Los Robles Hospital in Thousand Oaks, CA. He is also a clinical professor in emergency medicine and pediatrics at Olive View/UCLA Medical Center, a health law attorney with Boyce Schaeffer Mainieri, LLP, in Oxnard, CA, and the founder and CEO of Health-e-MedRecord, a patient-centered and emergency physician-designed EHR solution. ( Follow him on Twitter @carloreyesmdjd, and read his past articles at

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