Demonstrative Evidence


Demonstrative evidence can be very persuasive.   Research has shown that people remember what they hear much better when visual displays accompany the spoken word.1   Our society is becoming increasingly visually oriented.   Jurors who are accustomed to watching television, movies and videos on the Internet are prone to tune out evidence from witnesses without visual displays.

A good advocate must consider what demonstrative evidence will make his or her case more persuasive.  It is important to have a good understanding of the law as it relates to the admissibility of demonstrative evidence.


One of the most confusing things about the law relating to demonstrative evidence is the terminology.  Many different terms have been used by judges and legal commentators to describe different types of demonstrative evidence.   The terminology is not used consistently.

There are three types of evidence adduced at trial:  oral evidence from witnesses, documentary evidence and demonstrative evidence.   Demonstrative evidence is evidence that can be seen and viewed.    Some commentators use the term “visual evidence” as opposed to the term demonstrative evidence.2

There are two types of demonstrative evidence:  real evidence and illustrative evidence.

Real evidence is something that the trier of fact can use to draw inferences and conclusions from directly.  The authors of The Law of Evidence in Canada define real evidence as follows:3

When things are produced before the court, the court applies its own senses and draws conclusions.   The classification commonly used is “real evidence”…The term is used in a number of different ways, but in its widest meaning includes any evidence where the court acts as a witness, using its own senses to make observations and draw conclusions rather than relying on the testimony of a witness.

As Geoffrey Adair explains in On Trial, real evidence is on the same footing as oral evidence and documentary evidence in that the trier of fact can draw conclusions and make inferences directly from it:4

The drawing of conclusions directly from real evidence is the feature that such evidence shares in common with all other forms of evidence, including viva voce and documentary evidence.

Real evidence encompasses anything that the jury can look at and use to draw inferences and conclusions about the case independent of other evidence.  Some examples of real evidence include the following:

  • The gun used in a robbery.   The jury can look at the gun and make any number of inferences about the facts in dispute.
  • A photograph of damage to a vehicle.  The jury can look at the photograph and draw inferences about the nature and severity of the collision.5
  • A videotape of a robbery.   The jury can view the videotape and make a conclusion about the identity of the accused.6
  • An x-ray or MRI film.   The jury can view the films and draw conclusions about the nature and extent of the injury.
  • A photograph of a scar or injury.  A jury can look at the photograph and draw inferences about the nature or impact of the injury.7
  • A day in the life video showing the injured plaintiff carrying on activities of daily living or a defence surveillance video showing the plaintiff engaging in activities.   A jury can look at the video and draw conclusions about the plaintiff’s impairments and need for care.8

Illustrative evidence is used to illustrate, summarize or explain oral or documentary evidence.  The purpose of illustrative evidence is to make other admissible evidence easier to understand.  Unlike real evidence, the jury cannot use the evidence directly to draw conclusions.   Rather, illustrative evidence is intended to assist the trier of fact in understanding oral evidence or documentary evidence so that the trier of fact is in a better position to draw conclusions from the oral and documentary evidence.

The authors of a helpful American article on the subject describe illustrative evidence as follows:9

…any display that is principally used to illustrate or explain other testimonial, documentary, or real proof, or judicially noticed face.  It is, in short, a visual (or other) sensory aid.

The distinction between real evidence and illustrative evidence has been described as follows:10

Real evidence is used to help prove directly the existence of a fact of consequence in the action, where as demonstrative proof [or illustrative evidence] is only offered derivatively, to help explain or illustrate other admissible evidence.

Illustrative evidence is any visual aid that helps summarize, illustrate or explain other evidence.   Examples of illustrative evidence include the following:

  • Anatomical models and medical diagrams.   Models and diagrams can assist the jury in understanding complex expert evidence.11
  • Treatment charts.   A chart summarizing the treatment received by an injured person can help the jury understand and wade through voluminous medical records by summarizing the dates and nature of treatment received.12
  • Aerial photographs and maps.   While taken after the fact and not showing the scene as of the day of a collision, an aerial photograph can assist a jury in understanding lay and expert evidence as to what happened in a motor vehicle collision.
  • Scale diagrams.   A scale diagram showing an intersection, the involved vehicles and the distances involved can assist a reconstruction engineer in explaining his or her evidence to the jury.
  • Animations.   An animation showing the impact of degenerative arthritis on a joint can assist an orthopaedic surgeon in explaining future degeneration of the joint.   An animation of a collision can assist a reconstruction engineer in explaining his or her evidence to the jury.

Some commentators have objected to the characterization of illustrative evidence as “evidence” at all, preferring instead to refer to use the term “demonstrative aid” or “illustrative aid”.  Geoffrey Adair makes the following comments in On Trial:13

These “aids”, even though frequently marked as exhibits, no doubt for the sake of a complete record, do not constitute evidence in the classic sense.   The trier of fact is not free to draw independent conclusions from demonstrative aids but is only free to utilize same to better understand or remember the evidence of a witness from which the actual conclusions of fact will be drawn.

While illustrative evidence may not constitute evidence in the classic sense, it is filed as evidence and can be referred to by the trier of fact in the decision making process to assist in understanding all of the evidence.   Models, diagrams, charts and animations all become evidence once they are found to be admissible and marked as exhibits.


Justice Dickson made the following comments about the law of evidence in R. v. Abbey:[14]

The law of evidence, however, reposes on a few general principles riddled by innumerable exceptions….There are also exceptions to the exceptions.

With such a description, it may seem as though understanding the law pertaining to demonstrative evidence is a daunting task.   The key to understanding the law is to understand a few key general principles.   They are as follows:

1)               The demonstrative evidence must be relevant.

2)               The demonstrative evidence must be accurate and fair.

3)               The probative value of demonstrative evidence must outweigh any prejudicial effect of the evidence.

4)               The demonstrative evidence must not offend any exclusionary rule.

These four principles apply equally to real evidence and illustrative evidence.   For illustrative evidence, there is also an inquiry into whether the evidence is helpful in assisting the trier of fact understand facts and evidence.

These principles all foster the underlying goals of the law of evidence.   Those goals are to search for the truth, enhance efficiency in the trial process and to ensure fairness in the trial process.  As Barbara Legate points out in a helpful article on the law relating to demonstrative evidence, questions of admissibility should always be answered with these goals in mind:15

Evidence which meets these very fundamental goals ought to be admitted by the trial judge.  Demonstrative evidence which assists the trier of fact in the search for the truth, enhances the efficiency of the trial process and is not excluded because of overriding prejudicial effect is admissible using this approach.


Relevant evidence is that which is “logically probative”.16     Evidence is relevant if it has “some tendency” to make the proposition for which it is advanced more likely than the proposition would be in the absence of the evidence.17  The question is whether the evidence bears upon an issue in dispute.   Relevance is to be assessed as a matter of common sense and logic.18

It is a basic principle of the law of evidence that relevant evidence is prima facie admissible.19   This principle applies to all forms of evidence, including demonstrative evidence.


Once it is established that demonstrative evidence is relevant the inquiry shifts to whether the evidence is accurate and fair.   As Geoffrey Adair states:20

The real evidence must be accurate, fair in the sense of an absence of intention to mislead and verified upon oath to the extent such verification is reasonably available.

For real evidence, the key to accuracy and fairness inquiry is establishing authenticity.

For a medical instrument used in an operation to be admitted into evidence in a medical malpractice case there should be evidence that the instrument tendered is the one that was used and that it has not been altered.

For a photograph or video to be admitted as real evidence, there must be evidence from a witness to establish that the photograph or video accurately and fairly depicts what it purports to show.   It is not necessary that the photographer or videographer testify.   All that is required is some oral evidence to establish that the photograph accurately and fairly depicts what it purports to show.21

The evidence confirming the accuracy and fairness of a photograph or video may come from a person who witnessed what the photograph or video shows.   Sometimes there is no one who witnessed what the photograph or video shows (for example video taken from automatic video-surveillance).  As Justice Tobias pointed out in the case of R. v. Lahay, the evidence will be admissible if there is some evidence to show that the video is fair, unbiased and reliable:22

A long series of cases has established that the product of the automatic video surveillance is admissible as evidence so long as the framework in which it was produced can be shown to be fair, unbiased and reliable.

If a photograph or video does not accurate or fairly depict what it purports to show then it will not be admissible.   As Goldstein states in his text Visual Evidence, photographs and videos can be distorted in a way that renders them inaccurate or unfair and, thus, inadmissible:23

The image reproduced in the photograph, motion picture film, or videotape should be free from distortion and misrepresentation which could affect the admissibility and weight afforded the videotape.

If the distortion alters physical facts which are relevant to an essential or crucial issue in the case, then such distortion will go to the issue of the admissibility of the evidence and render it inadmissible.

Visual evidence, like any other kind of evidence, is subject to fabrication and falsification.  Photographs, films and tapes can be altered to misrepresent the facts.   Techniques such as editing, selective lighting, retouching, camera angle and multiple exposure can be employed to modify the picture image.   The resulting evidence is misleading because it creates a false impression in the mind of the trier of fact.

The requirement for accuracy and fairness applies equally to illustrative evidence.   For a medical illustration to be admitted into evidence, there must be oral evidence to confirm that it is an accurate and fair depiction of what it purports to show.   For a treatment chart to be admitted into evidence, it must be an accurate and fair summary of oral or documentary evidence.

In Owens v. Grandell these same principles were applied in relation to an animation illustrating a reconstruction of a motor vehicle collision:24

If proven to be accurate, then it should be admitted like any other piece of demonstrative evidence, such as a chart or map…Overall it must be proven that the procedures used to feed the data into the computer were reliable and that someone checked the accuracy of the data and the computer operations…The court must be careful not to attach undue weight to evidence that might confuse, mislead, or overwhelm the trier of fact.

 Whatever the form of demonstrative evidence, there must be oral or documentary evidence to confirm that it is accurate and fair.


There is a judicial discretion to exclude evidence that has a prejudicial effect outweighing its probative value:25

The occasions are frequent upon which a judge trying a case with the assistance of a jury is called upon to determine whether or not a piece of evidence technically admissible may be so prejudicial to the opposite side that any probative value is overcome by the possible prejudice and that therefore he should exclude the production of the particular piece of evidence…The matter is always one which is difficult for the trial judge an in itself essentially a decision in which the trial judge must exercise his own carefully considered personal discretion.

 As Ms. Legate points out, demonstrative evidence is prejudicial when it causes the jury to lose objectivity:26

It would appear that to be prejudicial, some demonstration that the jury would take leave of its objectivity should be shown.

The argument that a jury should not see a photograph or other piece of demonstrative evidence because it is too graphic is a difficult one to make.   As Justices Sopinka, Lederman and Bryant point out, demonstrative evidence is rarely found to be inadmissible on this basis:27

Circumstances in which a judge in a civil case would exclude evidence because of its inflammatory nature would be rare.   People today, because of their exposure to television and motion pictures, can be expected to be much less sensitive to graphic displays of injuries than the average nineteenth or early twentieth century citizen.

 In deciding to allow autopsy photographs to be admitted into evidence on a murder trial, Justice Doherty made the following comments:28

I have considerable difficulty in accepting the submission that the photographs had any significant potential to inflame the jury against the appellant.  Clearly, the jurors would routinely see much more graphic pictures and photographs in the popular media.

The judicial discretion to exclude evidence based on its prejudicial effect outweighing its probative value is a cost-benefits analysis.   Where the demonstrative evidence is of marginal relevance, it is more likely excluded.


Like the other forms of evidence, demonstrative evidence must not offend any of the exclusionary rules of evidence.

Where demonstrative evidence is sought to be introduced through a witnesses who is not the primary source for all of the facts depicted or conveyed in the evidence, hearsay issues may arise.  This was the case in R. v. Zundel29 where a motion picture film made during the liberation of Nazi concentration camps was tendered by the prosecution.   The film contained a narrative and the narrator was not made available for cross-examination.   The Court admitted the video but determined that the narrative was inadmissible hearsay.                 

Illustrative evidence is often adduced to help explain expert evidence. For the illustrative evidence to be admissible, the expert evidence that is exists to explain and illustrate must also be admissible.

In the case of R. v. Mohan,30 the Supreme Court set out a number of principles applying to expert evidence.   The Supreme Court indicated that expert evidence should only be admitted where it is relevant and necessary (in terms of assisting the trier of fact).   The Court indicated that the principles of relevance and necessity would be strictly applied where the expert evidence was on the ultimate issue to be determined:

24.   There is also a concern inherent in the application of this criterion that experts not be permitted to usurp the functions of the trier of fact. Too liberal an approach could result in a trial’s becoming nothing more than a contest of experts with the trier of fact acting as referee in deciding which expert to accept.

 25     These concerns were the basis of the rule which excluded expert evidence in respect of the ultimate issue. Although the rule is no longer of general application, the concerns underlying it remain. In light of these concerns, the criteria of relevance and necessity are applied strictly, on occasion, to exclude expert evidence as to an ultimate issue.

Given this statement, it is reasonable to conclude that illustrative evidence that bears upon the ultimate issue to be decided (such as animations of a collision in a motor vehicle case) will be more closely scrutinized than more mundane forms illustrative evidence.


Some commentators have suggested the in addition to meeting all the other requirements for admissibility that illustrative evidence must also be proven to be necessary or helpful in illustrating or explaining other evidence.  Geoffrey Adair states that the party tendering the illustrative evidence must:31

Satisfy the court that the use of the demonstrative aid is reasonably necessary to help illustrate or explain the evidence of a live witness.

 Barbara Legate suggests that the following questions be asked:32

Does it aid the trier of fact in the search for truth?

  •   by supporting the evidence of a witness, explaining or corroborating other evidence,
  • providing detail of a relevant issue,
  • assisting in the determination of a witness’ credibility,

Does the evidence tendered enhance the efficiency of the litigation process?  (by saving time, explaining or illustrating complicated or lengthy evidence, focusing testimony, and enhancing the ability of the trier of fact to come to a decision.

As Ms. Legate points out, the “helpfulness” inquiry should also consider the benefits of illustrative evidence:

Evidence must be relevant but [there] must be limits placed upon the evidence that can be adduced at trial to ensure the attainment of the goal of efficiency.   Evidence should not only be excluded under this heading but should be permitted if it enhances the attainment of the goal of efficiency.   Surely, enhancing the retention of information by the jury, the summarization of large amounts of information in an understandable fashion, the unravelling of complexities through the use of visual aids, and assisting the witness in explaining his or her testimony, all add to the ultimate goal of the process.

Probably of greatest concern in the current environment of trial delay, backlog and excessive trial duration, is the ability to use any device that will shorten the length of the trial in a fair and reasonable fashion.   Good demonstrative evidence can accomplish that.

The helpfulness criteria will be easily met for most forms of illustrative evidence.  Treatment charts are a helpful summary of voluminous medical records.   Medical illustrations and animations make it much easier for medical and engineering experts to explain what they are talking about.  This evidence tends to improve the efficiency of trials and make it easier for juries to understand complicated oral and documentary evidence.

  1. See Elliot Goldstein, Visual Evidence: A Practitioner’s Manual (Toronto: Carswell, 1991), at 1-2.
  2. 2.      Ibid.
  3. Sopinka, Lederman and Bryant, The Law of Evidence in Canada 2nd ed. (Toronto: Butterworths, 1999), at p. 17.
  4. Geoffrey Adair, On Trial:  Advocacy Skills Law and Practice, 2nd ed. (Toronto:  LexisNexis Canada, 2004), at p. 24.
  5. See Rodger v. Strop, [1992] O.J. No. 2769 (Gen. Div.).
  6. R. v. Nikolovski (1994), 19 O.R. (3d) 676 (C.A.).   In this case, the Court held that a video-tape, without any corroborating evidence, could provide the necessary evidence to establish identity.
  7. See Draper v. Jacklyn (1970), 9 D.L.R. (3d) 264  (S.C.C.).   The plaintiff sought to introduce photographs of the plaintiff’s face which showed the condition of scarring and showed two Kirschner pins sticking out of the plaintiff’s head to hold fractured bones together.   The Court held that the photographs were relevant and admissible.
  8. See Teno v. Arnold (1974) 7 O.R. (2d) 276, at 297 (H.C.J.).   In the trial decision, Justice Keith admitted a day in the life video into evidence.  Justice Keith said the following about the video:   “I cannot conceive of a more graphic portrayal of what I must try to express in words”.   See also Rodger v. Strop, supra, note 5.
  9. Brain and Broderick, “The Derivative Relevance of Demonstrative Evidence:   Charting its Proper Evidentiary Status” (1992) 25 U.C. Davis L. Rev. 957, at 968.
  10. Barbara Legate, “The Admissibility of Demonstrative Evidence in Jury Trials: Applying the Principled Approach to the Law of Evidence” Paper Delivered to OBA Central East Advocacy Conference, May 1, 2004.
  11. See Majcenic v. Natale, [1968] 1 O.R. 189 (H.C.).
  12. See Calic v. Aitchison, [1996] O.J. No. 154 (Gen Div), at 19.   Justice Hockin commented that the plaintiff’s medical history was lengthy and complicated and that “counsel for Mr. Calic usefully summarized the history by tracing Mr. Calic’s five year journey from one specialist to another in documentary form exhibit”.
  13. Supra, note 4, at p. 26.
  14. [1982] 2 S.C.R. 24, at 40.
  15. Barbara Legate, supra, note 10.
  16. R. v. Nikolovski [1996] 3 S.C.R. 1197, at p. 1206.
  17. R. v. J.-L.J., [2000] 2 S.C.R. 600, at p. 623.
  18. Sopinka, Lederman and Bryant, The Law of Evidence in Canada, supra, note 3, at p. 24.
  19. Ibid.  See also R. v. Watson, (1996) 30 O.R. (3d) 161, at p. 176.
  20. Geoffrey Adair,  On Trial:  Advocacy Skills Law and Practice, supra note 4, at p. 25.   See also Sopinka, Lederman and Bryant, The Law of Evidence in Canada, supra, note 3 at p. 19.  
  21. Sopinka, Lederman and Bryant, supra, note 3, at p. 19.
  22. R v. Lahay, [1995] O.J. No. 4299 (Gen. Div.).
  23. Goldstein, supra, note 1, at p. 2-17, 2-18.
  24. Owens v. Grandell, [1994] O.J. No. 496 (Gen. Div.).
  25. Draper v. Jacklyn, [1970] S.C.R. 92.   Photographs showing the injury to the plaintiff’s face were admitted.
  26. Legate, supra, note 10, at p. 13.
  27. Sopinka, Lederman and Bryant, The Law of Evidence in Canada, 2nd ed., supra, note 3.
  28. R. v. Wade (1994) 18 O.R. (3d) 33 (C.A.), at p. 40-41
  29. (1987) 58 O.R. (2d) 128 (C.A.).
  30. R. v. Mohan, [1994] 2 S.C.R. 9.
  31. Geoffrey Adair, On Trial, supra, note 4, at 29.
  32. Legate, supra, note 10, pp. 10-11


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Troy Lehman joined Oatley Vigmond in 2006 and became a partner in 2010. As a personal injury lawyer, his greatest satisfaction comes from helping people through to the other side of a difficult time in their lives. “We’re here to help and relieve stress,” Troy says. “When I walk into a first meeting with a client, people are often scared and anxious. And for me, the best thing that can happen at the end of the meeting is that they say, ‘I feel so much better.’

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