A. GENERAL RULES OF ADMISSIBILITY
Demonstrative evidence, or evidence that is admitted as a testimonial aid rather than as substantive evidence, 4 may include maps, plats, charts, drawings and diagrams - none of which are real evidence themselves but, rather, are depictions or illustrations by which means witnesses may more clearly describe factual situations and the trier of facts may more clearly understand their descriptions. If graphics are introduced solely for the purpose of illustrating the testimony of a witness, that purpose should be made clear on the record and the court should instruct the jury that the graphics are not to be considered as evidence, but merely as an aid in evaluating evidence. 5
Although almost universally present in contemporary jury trials, there is no uniform treatment concerning the admissibility of demonstrative evidence. Historically, common law regulation of evidence permitted the use by a witness of demonstrative evidence, which was governed by judges' "common sense and fairness in view of the particular circumstances." 6 This view has been carried into the modern era of code-based regulation, with demonstrative evidence generally used at trial subject only to the sound discretion of the trial judge. 7
Graphics that are introduced as demonstrative evidence may be made by the witness while testifying, either by his own hand, by directions of counsel, or made prior to trial either by counsel or another. Such demonstrative evidence will generally be admitted into evidence despite a hearsay objection so long as it is properly verified and shown to be reasonably accurate, correct, relevant and able to assist the jury in understanding the testimony. Although there is little authority as to when a judge will exercise his discretion to rule a graphic inadmissible, Federal Rules of Evidence 401 through 403 (and corresponding state rules) do allow the trial court to preclude individual exhibits that are not properly authenticated or relevant, or are deemed to be unfairly prejudicial, inaccurate or incomplete.
i. Authentication
The touchstone for admissibility is proper authentication. So long as a qualified witness (i.e. a witness shown to have personal knowledge of the facts) is able to testify that the graphics are an accurate, reliable, complete and fair representation, it is irrelevant that they did not prepare them personally. 8
The question of whether the graphics have been properly authenticated seldom arises when the drawing is made by a witness while testifying, since the act of making the drawing under oath is a sufficient deposition that it is a true representation to their knowledge. If, however, the witness is making the drawing at the request of counsel, he should be shown to have the requisite knowledge. Similarly, if a graphic is offered in evidence on the testimony of a witness who did not prepare it himself, his personal knowledge of the represented facts must be adequately shown.
ii. Accuracy
In general, demonstrative evidence such as diagrams and charts may be entered into evidence provided they fairly and accurately represent that which they purport to depict. 9 The finding of correctness for admissibility is again within the sound discretion of the trial judge, though graphics that are used merely to illustrate the testimony of a witness will not be subject to as strict a proof of accuracy as those offered as independent evidence. Admissibility will generally rely on whether there is enough evidence of its correctness to entitle it to be used, rather than whether it is entirely correct, and a judge's decision to admit a graphic is in no way binding upon the parties or the jury on the issue of correctness. 10
The possibility that a graphic such as a map incorporates inaccuracies will therefore generally not prevent its authentication or admissibility, but rather pose a question of what weight the jury will afford it. 11 The opposing party may discredit the graphics by showing the interest of the witness, or by introducing evidence of defects in it, either in cross-examination or by rebutting evidence. In Bassett v. Pennsylvania R. Co., 12 the court overruled an objection to the admissibility of an engineer's plan on the grounds of being based on vague, indefinite and insufficient data, stating that "the accuracy of the data and of the plans, like the credibility of the witness who made it, was for the jury. It was the result of the engineer's work, showing what he had testified to on the stand, and was […] clearly competent."
iii. Completeness
As a general rule, the admission of a graphic does not depend on its being complete. It is not necessary that it represent the entire object or area that may be material to the issue. When counsel does introduce a graphic, however, that is not totally complete or accurate, it would be prudent to advise the jury that the exhibit is being used simply as a visual aid. For example, in the case of Commonwealth v. Trudell, 13 the use of an incomplete flow chart was deemed admissible where the trial court carefully instructed the jury regarding the accuracy and shortcomings of the chart.
iv. Unfairly Prejudicial
In general, objections made to a drawing on the general ground that its design or character is unfairly prejudicial are usually overruled, and there are few decisions in this class. In Commonwealth v. Crawley¸ 14 the trial court was held to have properly admitted body charts prepared by a detective showing the location of wounds in a prosecution for murder, robbery, and rape, finding the sketches and charts were neutral, dispassionate, and in no way inflammatory. In a New York prosecution for arson, a map of buildings in the block with the one alleged to have been set on fire by the defendant was also held admissible. 15
One situation where the courts have agreed in finding graphics inadmissible on grounds of creating an erroneous impression in the minds of the jury is when different scales or disproportionate representations are used. In Litts v. Wayne Paving Co., Inc. 16 the court was found to have not abused its discretion in refusing to permit into evidence two exhibits concerning the topography of a road on which an accident occurred, which were drawn to different scales. Courts do, however, tend to admit individual graphics that are not drawn to scale if it is specified that they are only being used for demonstrative purposes and the witness who is using it can testify to the correctness of the graphic in the respect for which it is being used. 17
Similarly, courts may render an otherwise valid exhibit inadmissible if it contains prejudicial or conclusory terminology, oftentimes considered highly prejudicial by the courts. 18 Examples include the term "overstated" written on a chart that referred to the expenses claimed by defendant on a tax return, 19 and other similar terms relating to tax matters, such as "unreported net income," and "overestimation of expenses."
v. Irrelevant or Unnecessary
Rule 402 of the Federal Rules of Evidence states that "[e]vidence which is not relevant is not admissible." Counsel may challenge the admissibility of a graphic on the ground that it is not relevant to the proposition for which it is offered - thereby challenging the conclusion expressed in the exhibit rather than its accuracy. The success of such a challenge will usually fall on the ability of opposing counsel to show that the prejudicial effect of admitting the graphics greatly outweighs any evidentiary value.
Rule 403 also notes that, even if relevant, evidence may be excluded "by considerations of undue delay, waste of time, or needless presentation of cumulative evidence." Courts that are bound by this Rule may exclude graphics if found to be unnecessary and of no added assistance to the jury, 20 but will typically allow them so long as they are found to be of reasonably adequate assistance to the jury and not unduly prejudice it. In State v. Ray, 21 the court held that so long as the anatomy charts sought to be introduced will aid the jury in following a doctor's testimony, sound discretion would allow their use.
vi. Based on Inadmissible Evidence
Summary charts that are based on purely testimonial evidence 22 are generally allowed under Rule 611(a), under which a court is required to exercise reasonable control over the mode and order of interrogating witnesses and presenting evidence so as to make the interrogation and presentation effective for the ascertainment of the truth and avoid needless consumption of time. The trial judge again has the discretion to admit summary charts pursuant to this Rule so long as they are found to enable the jury to better understand the claims and significance of the facts or figures it might find correct from the evidence. 23 Aside from the grounds for objection noted above, however, summary charts may also be objected to and ruled inadmissible if they are not based on underlying admissible evidence. 24 A failure to connect the underlying information with the calculations on the chart may also jeopardize the chart's admissibility into evidence. 25
Ron Kurzman, Esq., is a Member of Magna Legal Services, LLC. He is an expert in assisting counsel in developing trial strategy for large, complex matters, based on behavioral research and jury analysis. As a litigation and trial consultant his activities include the development of trial strategy and tactics, jury selection and voir dire, implementing shadow juries, witness communication training, ordering of evidence, opening /closing statements, development of themes and arguments, demonstrative evidence preparation, and teaching persuasion techniques. He works with members of the trial team to develop themes and case strategies that will be persuasive to juries, judges and arbitration panels.