GPSolo Magazine - March 2004

Trial Practice
The Admissibility And Use Of Demonstrative Aids

Evidence can be classified in two broad categories: “demonstrative evidence” and “substantive evidence.” Demonstrative evidence is “that evidence addressed directly to the senses without intervention of testimony.” Such evidence is concerned with real objects such as charts, graphs, videotape, and computer animation, which illustrate some verbal testimony. This type of evidence carries no independent probative value, and its primary purpose is to illustrate the testimony of a witness to help the jurors understand difficult factual issues.

In contrast, substantive evidence is evidence “adduced for the purpose of proving a fact in issue, as opposed to evidence given for the purpose of discrediting a witness, or of corroborating his testimony.” An example is a computer simulation or reconstruction of an accident where scientific and other factual data is entered into a computer that processes the data and generates a visual image of how the accident must have occurred. The results of a simulation are dependent on the application of scientific principles and mathematical calculations, and are treated by the courts like other scientific tests that require proof of the scientific principles and data before it is admitted.

An animation, by contrast, is only demonstrative because it is merely a graphic, dynamic depiction of a witness’s testimony, and while it may recreate an event, the validity of the conclusion does not depend on the proper application of scientific principles, but rather on the witness’s testimony. Computer animation is the most sophisticated demonstrative evidence presentation system available to litigators today. It is especially useful and persuasive to illustrate expert opinions and in cases with complex and technical issues involving motion and perspective, such as the typical aircraft accident.

While the same requirements for foundation and test for admissibility apply whether the demonstrative evidence is computer generated or not, courts also recognize a computer animation’s dramatic effect and inherent potential to mislead or confuse the jury, and thus require prior proper disclosure and opportunity to object, often giving jurors cautionary instructions. In addition to compliance with prior disclosures regarding its intended use, computer-generated evidence must also be authenticated under Federal Rules of Evidence (FRE) 901 and 902, and it is subject to general evidentiary standards of relevancy under FRE 401 and 402 and fairness under FRE 403. Because each state has adopted its own evidence code, admissibility standards will differ among them.

Untimely, disclosure to opposing counsel and to the court of the intent to use computer-generated exhibits will almost certainly result in their exclusion. “As with all other exhibits, the court should afford each party an adequate opportunity to review and interpose objections to demonstrative evidence before it is displayed to the jury.”

Some evidence pertinent to aviation litigation, such as FAA or NTSB data used in an aircraft accident reconstruction, for example, is selfauthenticating. Most other evidence requires a proper foundation, and proposing counsel must first establish the authenticity of the exhibit by evidence sufficient to support a finding that the matter in question is what it purports to be. This is accomplished by a witness who has personal knowledge of the exhibit’s subject matter and testimony by that witness regarding the exhibit’s accuracy.

Once the proper foundation is established, the exhibit must be shown to be relevant to a material issue in the case. All relevant evidence is admissible unless a statute or rule proscribes it. An animation of the accident sequence would almost always be relevant in an aviation accident case, and thus highly unlikely to be excluded on a relevancy objection. But even highly relevant evidence will be excluded under Rule 403 if “its probative value is substantially outweighed by the danger of unfair prejudice, confusion of the issues or misleading the jury, or by considerations of undue delay, waste of time or needless presentation of cumulative evidence.”

In Daubert v. Merrell Dow Pharmaceuticals, Inc., the Supreme Court stated that as “gatekeepers,” the district courts must “ensure that any and all scientific testimony or evidence admitted is not only relevant, but reliable,” and set forth several factors to be considered in determining admissibility. The more recent Supreme Court decision in Kumho Tire Co. v. Carmichael clarified the scope of Daubert, holding that Daubert applies to all expert testimony, not just scientific testimony, and that trial courts should consider each of the Daubert factors “where they are reasonable measures of the reliability of expert testimony.” But where a demonstrative evidence exhibit is otherwise authenticated, courts have held that because an animation merely illustrates and is based on the witness’s testimony, instead of math and science, it is not substantive evidence, and thus there are no Daubert, Frye, or Rule 702 implications.

Courts have recognized the value of computer animation in assisting the trier of fact in understanding the technical and complex issues usually present in aviation accident cases, but are also aware of their potential to mislead or confuse, and will generally permit admission along with appropriate cautionary instructions.

Animation is not only useful in effectively illustrating and assisting the jury in understanding the technical and complex issues often present in aviation cases, but its use can be highly effective on other viewers as well. In Salvatore v. Valuejet (an unreported case), the defendant airline decided to settle the case after “animators . . . allowed jurors to feel the terror of the three and a half minutes it took (the defendant’s) plane to fall from the sky by animating the flight path of the plane and synchronizing it with the cockpit voice recording.” Computer animation is useful beyond the courtroom to effect settlements, and it is a weapon of choice in a litigator’s arsenal.

Whether used to aid the jury in understanding the technical and complex issues often present in aviation accident litigation, or to facilitate a favorable settlement, the use of computer-generated demonstrative evidence in this digital era is practically a must for the successful aviation litigator. To ensure its admissibility, the litigator must keep in mind the reasons for which computergenerated evidence is being proffered. Whether computer-generated evidence is offered as substantive or demonstrative, counsel should ensure its admissibility, thereby assisting the trier of fact to understand the difficult issues and permitting counsel to take advantage of the tremendously persuasive power of digital imaging as evidence of reality.

Steven C. Marks is a partner at the law firm of Podhurst, Orseck, Josefsberg, Eaton, Meadow, Olin & Perwin, PA, in Miami, Florida.

For More Information About The Tort Trial And Insurance Practice Section

- This article is an abridged and edited version of one that originally appeared on page 24 of The Brief, Summer 2003 (32:4).

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