How can expert witnesses and the attorneys who employ them effectively use demonstrative evidence to present expert testimony?


Trial attorney Karen Koehler explains.


Q. Attorney Koehler, how important is demonstrative evidence to effective presentation of expert witness testimony?


There’s an old Chinese proverb that goes like this:  “Tell me and I’ll forget; show me and I may remember; involve me and I’ll understand.”   The same holds true when presenting expert testimony.


Q. How can experts assist counsel with demonstratives?


As soon as you figure out what the case is about, begin to work with the attorney to conceptualize what aids/evidence will be helpful.  Make suggestions.  When shown items, make sure they are accurate and capable of being understood.  Look at everything from the opposite perspective.   If the aids/evidence is more helpful for the other side …scrap them.


Q. What demonstratives work best in personal injury actions?


Materials that do not look like they have been manipulated.  Juries are savvy about photo shop. They are suspicious and will be looking to see if you are trying to game them.   Big cases warrant expensive demonstratives like re-creations.  Using expensive aids in smaller cases may backfire.  Sometimes the best aids don’t cost anything.   I once cross examined a medical expert with a paper cup, water, and my raincoat.  It worked beautifully.



Q. What horror stories can you relate as to demonstrative evidence going “bad” at trial?


Expert powerpoints are generally poor.  They are too detail oriented, usually made with preformatted templates, impossible to read, and confusing.  Experts spend so much time making sure their testimony will be technically correct, that they forget how important it is to K.I.S.S. the jury/judge.


Attorney Koehler will be speaking at the SEAK National Expert Witness Conference to be held on May 3-4, 2014 in Orlando, FL.


Demonstrative Evidence and Expert Witnesses

Karen K. Koehler Esq.

Attorney Koehler will explain how attorneys use demonstrative evidence with expert witnesses to persuade a judge and jury. She will also show how to maximize damages using demonstrative evidence. She will demonstrate, with the use of video, models, and a computer, how to simplify complex issues so that they are easily understandable for juries. Attorney Koehler will discuss the expert’s role in preparing and working with demonstrative evidence in a personal injury action. Attorney Koehler will give practical suggestions for how experts and attorneys can work together to persuade juries in 2013 and beyond.


Karen K. Koehler Esq. is a trial lawyer with the Seattle law firm of Stritmatter Kessler Whelan Coluccio. Nicknamed “The Velvet Hammer™” by some of her adversaries, Karen is known for her creativity, tenacity and trial skills. Few plaintiff attorneys try more cases than Karen. Atty. Koehler is a prolific speaker and writer, an author of nationally published legal treatises and an adjunct professor at the University of Washington School of Law. She has also gained national and local recognition from many, including the American Bar Association for maintaining a Top 100 “Blawg.” In addition to serving as President of the Washington State Trial Lawyers Association (2007-08), she has held leadership positions in the American Association of Justice. A member of the America Board of Trial Advocates, she is listed in The Best Lawyers in America, regularly listed as a Super Lawyer and a top 40 personal injury lawyer by Washington Law & Politics Magazine. She also won a trial lawyer of the year award in 2005.