Solid planning key to cross-exam of experts

Solid planning key to cross-exam of experts
This is the seventh instalment of Arguably the Best, our year-long series on improving your litigation skills.
Cross-examination of an expert witness is one of the most challenging and intellectually invigorating tasks presented to a litigator. We all remember what we learned in law school evidence classes about the goals of expert cross-examination (impeach the expert on relative expertise, misunderstanding of the facts, or improper assumptions). However, effective cross-examination of an expert requires careful preparation and courageous execution in order to accomplish those goals.

Learning and planning are the keys to preparation for the cross-examination of the expert; smart and confident conduct are the keys to execution of the cross.


Learn your own case first. Make sure you have a meticulous grasp of the facts relevant to the questions to be addressed by the expert. You should be the expert as to the facts of the case and you should never allow the expert an advantage in this area.

Learn as much as time (and your client’s retainer) allows about the expert’s field. You will never understand the topic to the depth the expert does, but if you handle the cross-examination properly, you won’t need to do so. At the outset, become fluent in the terminology of the field. Read about the equipment used and standard textbooks of the field. Define for yourself the parameters and limitations of the discipline, its controversies, and settled understandings.

Learn as much about the expert as is relevant to the opinion offered. Read her published articles and reported cases. Ask your colleagues about previous experiences with the expert in court or on discovery. Find out where your expert went to school, the nature of his professional experience, where she stands on the controversial issues, the nature of his practice and personality.


Before you think of a single question for the expert, set out clearly for yourself the goals and objectives of the cross. Be realistic about what you can accomplish. The expert is a professional with a reputation on the line, who has given thought to the matter, and is not going to abandon a stated and considered conclusion easily (unless refusing to do so makes her look worse).

Consider the best possible outcome of the cross relative to your case and work backwards towards the milestones you will have to pass along the way to get there. Some of these milestones might represent the end of the road once your cross gets underway, and you should decide the bare minimum concessions with which you will be satisfied.

Keep the milestones and ultimate objectives in mind once you begin to plan. Draft your plan in some documented form.

For crucial questions, consider the range of possible answers and be prepared to follow up on every single one.

Plan to proceed incrementally. Don’t try to get away with broad sweeping questions that overreach attainable goals. Consider how to solidly establish the points you wish the expert to concede through the course of the cross, like beachheads to which you can retreat and from which you can advance again, in a different direction, if need be. Think about different routes to the same destination if the expert shuts the preferred one down. Plan to close off escape routes for the expert so he can’t retreat back past concessions already made.


The manner in which you conduct the cross-examination of the expert is as important as your plan.

Cross of an expert is not for the faint of heart. Experts can sense fear and will intimidate you with their superior knowledge if you let them. Never forget that the expert knows more than you do, but never let that show. Remember always that the expert — by agreeing to appear as a witness — has willingly submitted to the rules of court and evidence and those rules put you in control of the conduct of the examination.

Word your questions precisely without room for misunderstanding or for obfuscation on the part of the witness. Use what you learned in preparation to speak to the expert in the language of the field. Display your understanding of the science involved, not to show off, but to let the expert know that you are able to detect evasiveness.

Stick to your plan. Don’t be rude or disrespectful by interrupting the witness, but always make him return to the point of your question. Be flexible enough to adjust your plan as you go, to avoid unexpected pitfalls, and to follow up on unexpected concessions or your own “eureka” moments. Always be ready to adjust to account for the personality and demeanour of the expert — a refusal by a stubborn or arrogant witness to concede a clearly won point can be more valuable than an eager concession from a nervous witness just trying to get off the stand and back to the lab.

Keep an eye on the trier of fact. It is of no use to you or your client if you best the expert intellectually but no one notices.

The expert report and the testimony in chief will have already taken the judge or jury to the destination the adverse party wants them to go. A prepared and confident counsel who can take control of an expert in cross will be an inviting guide to the trier of fact. If you look like you know where you are going and can be trusted to get there, the trier will be willing to go with you. Just remember to look back over your shoulder and make sure she is following.

As with all aspects of litigation, preparation, and the confidence it brings, are the keys to success in cross-examining the expert witness. A well-conducted cross will make the hours spent in preparation worthwhile and may just be the key to winning your case.

Dan Boone is the regional managing partner of the St. John’s office of Stewart McKelvey. His litigation practice is focused on defence of hospital malpractice and personal injury claims and class actions.

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