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How To Effectively Attack & Defend Expert Testimony: Effectively Discrediting The Expert At Trial – Blog 8 Of 9

How to Effectively Attack & Defend Expert Testimony: Effectively Discrediting the Expert at Trial – Blog 8 of 9

Post Series: How to Effectively Attack & Defend Expert Testimony
  1. Effectively Presenting and Discrediting the Expert at Trial
    1. Effectively Presenting your Expert at Trial

In most cases, pre-trial posturing, motion hearings, depositions and mediation eventually result in settlement of even the biggest construction cases before trial.  Nevertheless, the trial lawyer evaluate the trial strategy, formulate the theme of the case, develop the story, and consider where and how the expert will fit in from the beginning of the case through trial.  Construction cases are often complex, and the risk of boring, confusing or losing the jury, or even the judge in a bench trial, looms large.  A winning trial strategy must include the effective presentation of expert testimony at trial.

An effective expert presentation takes a complex topic and explains it in terms that are understandable to the average layperson.  Too often experts are prone to rely upon technical jargon that may confuse or frustrate the trier of fact.  It is up to the trial lawyer to make sure the expert is prepared to testify in a manner the trier of fact can easily comprehend.

On direct examination, the trial lawyer should begin by stepping the expert through his or her qualifications and experience.  Do not let your opposing counsel stipulate that your expert is qualified if you have a particularly strong expert.  Ask the judge to allow you to proceed with establishing your expert’s qualifications so the jury can use that information in evaluating your expert’s credibility.

After reviewing your expert’s qualifications, it is usually best to start with the basics when presenting complex expert testimony. Once the qualifications are established, focus your questions on educating the trier of fact on the general subject matter at issue.  For example, if a construction defect case involves leaking curtain walls in a high-rise building, as discussed in our previous example, it is important to explain what a curtain wall is and how it is intended to function.  As the saying goes, a picture is often worth a thousand words.

Walking the expert through photographs or diagrams is an effective way to introduce the topic.  The trial lawyer may want the expert to identify a photograph of the building in question and point out the curtain walls, then have the expert generally explain how these types of window systems are intended to keep water out of the building.  Using a diagram or animation to reveal the inner construction of a section of the curtain wall and show how it is supposed to function allows the jury to better see and understand what the expert is describing.

Staying with the curtain wall example, most curtain-wall systems manage water infiltration by capturing water that penetrates past the gaskets and diverting that water into bottom sills where it will drain back to the outside through weep holes.  Use of photographs and demonstrative aids with the expert to show how the curtain wall functions is critical.  If your expert starts getting bogged down with technical terms or lengthy explanations, break down the testimony through your questioning.  Make the expert back up, explain the technical jargon, and point out the area on the photograph or diagram before moving on.  The jury will appreciate the effort to explain the subject matter before there is any discussion of the forensic testing performed in the case and the ultimate opinions of your expert as to why the curtain walls leak.  This also allows the jury to become comfortable that your witness is indeed an expert in the subject matter.

Once you educate the trier of fact on the basics, it is then appropriate to have the expert discuss the forensic testing protocol used and why.  For example, in our leaking curtain wall case the expert probably followed the ASTM E-2128 Standard Guide for Evaluating Water Leakage of Building Walls.  Have the expert describe the basic steps involved in this protocol, including the order and purpose of each step.  A step-by-step explanation is important because it demonstrates your expert’s working knowledge and will allow the jury to understand the testing program.

The ASTM E-2128 begins with obtaining the history of building leaks, including the frequency, locations, and conditions when leaks occurred.  If you represent the plaintiff, have your expert step through the leak history for the trier of fact before getting into the forensic testing details.  At this point, you have probably presented fact witnesses who described in detail the history of water intrusion.  Nonetheless, the expert’s testimony provides an opportunity to reinforce the history of water intrusion issues that have plagued the building. Stepping through the building history will also demonstrate to the trier of fact that your expert took the time to investigate the issues thoroughly before launching into an opinion.  Have your expert explain why an understanding of the leak history is important in selecting testing locations, and have the expert point out areas of historical leaks on photographs or diagrams so the jury can appreciate the extent of the water intrusion problem.

Next, have the expert explain what window testing was performed and why.  Have the expert explain how the expert’s forensic analysis is consistent with the recognized ASTM E-2128 forensic protocol.  The expert should also explain how the expert performed any specific testing and why.  For example, the expert can explain how an ASTM E-1105 chamber test is an effort to recreate leaks that previously occurred in nature to demonstrate there is an ongoing issue in that area.  Once again, photographs or video of the testing and resulting water intrusion help the trier of fact to understand the testing protocol and observe the evidence of leaks at window locations.

If your expert has any areas that may have some weakness, it is better to bring these out on direct and have your expert explain them away.  If you anticipate what your opponent will raise in cross-examination, you can better control the delivery and perception of potentially negative information. It will be much worse for the trier of fact to hear potentially negative information for the first time on cross-examination.  It may then appear your expert was being less than forthright and could damage your expert’s credibility.

Finally, your expert should deliver a strong statement of the expert’s conclusions and opinions.  Have your expert tie the opinions directly to the results of the forensic process.  Your expert’s opinions should seem an inescapable conclusion based on the facts and data presented.

  1. Effectively Attacking the Opposing Expert

How does the trial attorney effectively discredit an adverse expert witness at trial?  Remember, a Daubert hearing is not a substitute for vigorous cross-examination.  The first step in effectively attacking or discrediting an expert witness is to know as much as possible about the expert’s background and prior testimony in other cases.  Rule 1.280 (v)(5)(A)(iii), Florida Rules of Civil Procedure, provides the starting point for such an investigation.  Any party may obtain discovery of the following information from any person expected to be called as an expert witness at trial:  (1) the scope of employment in the pending case and the compensation; (2) the experts general litigation experience, including the percentage of work performed for plaintiffs and defendants; (3) the identity of other cases in which the expert has testified at deposition or at trial (within a reasonable amount of time); (4) an approximation of the portion of the expert’s practice that is dedicated to serving as an expert witness.  A Lexis or Westlaw search may also be helpful in obtaining published opinions where the court upheld or disqualified an expert’s opinion testimony.  However, keep in mind that published opinions infrequently report details of expert testimony.

Use of expert deposition data banks can be helpful in obtaining the expert’s previous deposition testimony.  Trial Smith and Lexis-Nexis Expert Research On-Demand are two sources to investigate the credibility of an expert witness and to obtain information for use in impeachment.  Lexis-Nexis includes testimonial searches, disciplinary searches, previous challenges to exclude the witness, procurement of transcripts and depositions from prior cases, searches of articles written by the expert and other valuable information.  The cost is often worthwhile, particularly for large construction cases.  Thorough research of the expert assists the attorney in determining if the expert has taken contrary positions in other cases and is an effective to tool to impeach the witness.  With respect to defending your own expert witness, performing similar background checks allows the attorney to evaluate potentially negative information and prepare to neutralize the effect to the extent possible.

Knowing the opposing expert’s background and prior testimony can provide useful impeachment material for trial.  Even when your research fails to unearth useful impeachment material, the trial attorney can nevertheless effectively cross-examine an opposing expert at trial.  An effective cross-examination should focus on establishing doubt as to the credibility of the expert or the reliability of the expert’s conclusions.

One key to effective cross-examination is control over the opposing expert during questioning.  The trial attorney must be careful to stick to leading questions and not allow the opposing expert the opportunity to repeat, and thereby reinforce, a potentially damaging opinion.  Effective cross-examination also starts well in advance of digesting the expert’s trial testimony on direct at trial.  After all, the trial attorney should already know the potential weaknesses from the opposing expert’s report and deposition testimony.  The trial attorney should lay the foundation for an effective cross-examination during the deposition of the opposing expert witness.  Cross-examination can and should be prepared in some detail before trial and then adjusted based on the direct testimony delivered at trial.

If the opposing expert is clearly qualified, it is best not to challenge the qualifications and thereby reinforce them.  Also, attempting to directly battle a well-qualified expert on the details of expert’s area of expertise can backfire.  No matter how well the trial attorney may know the case, a qualified opposing expert is likely to know more about the field of expertise.  Rather, an effective cross-examination should focus on leading questions designed to reveal what is missing from the expert’s experience or training, to expose what investigation or alternate tests the expert did not perform, and to call into question the validity of assumptions underlying the expert’s opinion that may not be completely accurate.

The attorney should also expose the limits of the expert’s experience, methodology and sampling size.  The trier of fact should know that the opposing expert lacks the detailed experience of your expert, if that is the case.  If the method used by your expert was more rigorous, you should bring that out on cross-examination.  If the opposing expert has done no testing and is only criticizing your expert’s testing, have the expert admit that he or she could have done their own testing and did not.  This will raise the inference that the adverse expert performed no additional testing because the expert did not want to expose the truth about the condition or risk confirming your expert’s findings.  Do not have the opposing expert repeat the expert’s opinion on cross-examination.  Instead, force the opposing expert to admit the limitations on his or her experience and methodology.  Remember, an effective cross-examination should sow the seeds of doubt in the minds of the trier of fact.

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