Demonstrative Evidence: Uses and Abuses

• Author: Roger G. Oatley
• Pages: 379-389

Demonstrative

Evidence:

Uses

and

Abuses

Roger

G.

Oatley*

A.

INTRODUCTION

It

has

always been

true

that

"a

picture

tells

a

thousand

words."

It

goes

without saying that

this

old

adage

is

just

as

true

in the

courtroom

as in

any

other arena

of our

lives.

Increasingly,

trial lawyers recognize

the

power

of

visual images

to

inform,

explain,

and

persuade.

All

forms

of

evidence have

the

capacity

to

assist

in the

search

for

truth

or to

mislead.

We

subject

oral evidence

to

cross-examination

in

order

to

test

its

accuracy.

But

visual images cannot

be

tested

by

cross-

examination

in the way

oral evidence

can be.

This

is all the

more

fasci-

nating

a

notion when

we

consider

the

great power

of

this

form

of

evidence. Much demonstrative evidence goes into evidence largely

untested.

Yet

demonstrative evidence, like oral

evidence,

has the

capac-

ity

to

mislead

and can be

abused.

In

this article

I

review some

of the

more common

forms

of

demon-

strative evidence,

namely,

computer animations, photographs,

and

charts

and

graphs,

and

explore

the

ways

in

which they

can be

used

and

their potential

for

abuse.

*

Of

Oatley,

Vigmond.

379