Expert witness visual aids fall under the umbrella of demonstrative evidence—referring to any exhibits that accompany and clarify trial testimony. Visual aids can make complex topics digestible to a jury and even change the tide in a courtroom. With a few guidelines, you can ensure you employ visual aids wisely and make your testimony as advantageous as possible.
Why Use Visual Aids in Court?
There’s truth in the old cliché “Seeing is believing.” When a fact-finder (juror or judge) can visualize what happened, it’s easier for them to connect the pieces of a case. Visual aids can also help fact finders evaluate damages.
Seeing is believing, but seeing is also retaining. For sighted individuals, approximately 85% of the information we take in is visual. Studies indicate that we also retain more of what we see. When we combine seeing and hearing, we retain up to 700% more information than when we only hear that same information.
Today’s juries expect that much of what they encounter in court will be visual. The popularity of TV shows like CSI and Law & Order often leads jurors coming to court primed for a visual experience. To a juror whose only legal experience is through streaming shows, the connection between “court” and “audiovisual” is a strong one. With visual aids, attorneys and experts can leverage that preexisting connection to provide better education and a bigger impact.
Understanding Demonstrative Evidence and Expert Testimony
Currently, no federal rule of evidence specifically governs demonstrative evidence. Nonetheless, courts often require that attorneys share expert witness visual aids created for trial as part of the discovery process. This makes it critical for attorneys to pay attention to deadlines for trial exhibits. These often apply to visual aids and other forms of demonstrative evidence.
Substantive Demonstrative Evidence
In the case of evidence, anything directly related to the case falls under substantive demonstrative evidence. An example of this is the mangled frame of an allegedly defective bicycle brought into the courtroom. Generally speaking, expert visual aids that supplement, teach or explain their testimony falls under the category of demonstrative visual aids.
Illustrative Demonstrative Evidence
By contrast, illustrative demonstrative evidence encompasses visual aids that are used solely to help the jury understand the arguments made. For example, a diagram showing how the metal used in the allegedly defective bicycle’s frame is smelted would be considered illustrative demonstrative evidence.
Possible Objections to Expert Witness Visual Aids
An expert witness’s visual aids may draw objections from opposing counsel, but attorneys can prepare for several avenues of attack. Start by addressing the issue of relevance: Is the visual aid relevant to the case overall and to the issues your expert will discuss? Attorneys prepare for objections based on Federal Rule of Evidence 901, concerning authenticity, or its state equivalents. If necessary, the attorney you’re working with will prepare for you questions that authenticate a particular expert visual aid.
Visual aids also tend to have a larger emotional impact than verbal testimony. But as such, many such aids may run afoul of FRE 403. This requires that evidence is more probative than prejudicial. Though it’s not always possible to “tone down” every visual aid, it is wise to double-check its factual basis. A focus group or other unbiased third party can help to ensure that a visual aid’s emotional impact is proportional to its evidentiary impact in the case.
Tips for Supplementing Expert Testimony With Visual Aids
In order to maximize any trier of fact’s experience with your expert visual aids, there are a few items to consider.
Keep it Simple
The more information packed into a visual aid, the less likely that the jury will absorb it all. Simple diagrams or clear photos can be far more effective than busy visuals full of fine print. Expert witness visual aids don’t need to be complex productions either. Many experts, particularly those teaching in their area of expertise, can effectively explain concepts with a whiteboard and dry-erase marker.
Leverage Presentation Tools
Explore ways to leverage the tools used to present the visual aid itself. For example, if an opposing expert uses a whiteboard to draw a diagram during direct examination, you can use this to your advantage. List the specific points to which the expert does or does not agree during cross-examination on that very same whiteboard for maximum impact.
Don’t Shy Away From Tech, When Appropriate
In some cases, an animation or 3D reproduction may help create a more immersive experience for the jury. Let’s say, for example, the case involves a murder shooting. An animated simulation would be an effective medium for a forensic ballistics expert witness to convey the bullet’s trajectory. The same concept can apply to a range of cases and expert specialties. Accident reconstruction experts can model crash scenes. Medical experts can model injuries and treatments using 3D computer programs.