"Demonstrative evidence is admissible material used to illustrate a witness’s testimony or make other evidence more comprehensible…" (G. Christopher Ritter. Creating Winning Trial Strategies and Graphics, ABA, 2004.) It must meet the requirements of all illustrative material used in court:
► not violating any substantive rule of evidence,► relevancy, and
► fairness and accuracy.
In addition, in order to be admissible, demonstrative evidence is based on underlying data that is:
► too voluminous to be conveniently examined in court,► independently admissible, and
► made available to opposing counsel prior to the use of the exhibit.
Timelines are good examples of admissible demonstrative evidence because they graphically summarize a large number of significant events. The following timeline was created to show the proactive role of a defendant in protecting its employees against harassment. It was presented in two formats: 1) a static display on exhibit board that was in view throughout the proceedings; and 2) an interactive AV presentation that included supporting exhibits and videotaped testimony.
The timeline was prepared using data taken from exhibits that were jointly introduced by the parties. Opposing counsel received a printed copy of the timeline well before the proceedings started. At the conclusion of several days of testimony, the timeline was admitted as an exhibit (over the objections of opposing counsel).
