Encyclopedia of Psychology and Law

Voices may easily be disguised, further decreasing

the ability of a witness to accurately recognize a

voice. When a witness hears a voice raised in anger

during the commission of a crime and subsequently

attempts to recognize the speaker saying something in

a normal tone, accuracy is decreased. Whispering is

an extremely effective way to disguise a voice,

because it covers up many distinctive vocal character-

istics such as pitch.

Earwitness accuracy may also be related to the age of

the witness. Studies tend to show that very young

children are not as accurate in recognizing voices as

children above 10 years of age, who often perform com-

parably with adults. Speaker identification accuracy also

decreases after the age of 40, probably related to

increases in hearing loss for older persons. Furthermore,

blind persons are not superior to sighted persons in their

ability to recognize voices or other natural sounds, in

spite of popular opinion to the contrary.

Common sense tells us that recognizing the voice of

an acquaintance, friend, or family member should be

easier than recognizing the voice of a stranger. To a cer-

tain extent, research supports this conclusion. However,

studies of the recognition of familiar voices find a wide

range of accuracy levels, depending on the specific cir-

cumstances of the event. Although some studies find a

high degree of accuracy (more than 95%) in recogniz-

ing familiar voices, studies often show accuracy rates of

less than 70%, and sometimes significantly lower.

Daniel Yarmey and colleagues, for example, compared

participants’ recognition of highly familiar voices

(immediate family members or best friends), moder-

ately familiar voices (co-workers, teammates, or

friends), or low-familiarity voices (casual acquain-

tances) and found that accuracy for identifying voices

of low and moderate familiarity was only about 65%

and participants misidentified the voices of strangers as

being familiar almost 40% of the time. Thus, according

to Yarmey, when a witness claims to recognize a perpe-

trator’s voice as that of a familiar person, police officers

should not simply take this statement at face value but

should construct a voice lineup to test the witness’s

ability to identify the voice in question.

Unfortunately, the most salient indicator of voice

recognition accuracy for a juror is often the witness’s

confidence in the courtroom. Studies consistently

show that voice identification accuracy is almost com-

pletely unrelated to confidence. Extremely confident

witnesses are often wrong in their identification of a

voice, and accurate witnesses often show little confi-

dence in their identifications. Furthermore, jurors are

likely to overestimate the likelihood of any voice

identification being accurate. When psychology

students, for example, are asked to estimate the per-

centage of accurate identifications in circumstances

mirroring actual laboratory and field studies, they

consistently give unrealistically high accuracy predic-

tions. While it may not be surprising that laypersons

have little knowledge of the problems associated with

earwitness identification, a recent British study indi-

cated that police officers were no more knowledge-

able than the general population regarding voice

recognition issues.

Voice Identification Procedures

In another parallel with eyewitness research, the use of

one-person showups in voice identification has been

criticized as unduly suggestive. In a study by Daniel

Yarmey and his associates, a young woman approached

citizens individually in a public place and interacted

with them for about 15 seconds each. The participants

were given a voice identification test approximately

5 minutes after the encounter. When the test was a one-

person showup as opposed to a lineup to six voices,

innocent suspects were significantly more likely to be

identified. Accurate identifications of the real speaker’s

voice were rare in both conditions.

Within the United States and, for the most part,

internationally, there are few standardized procedures

for use in forensic voice identification. Researchers at

the Netherlands Forensic Institute have proposed the

development of guidelines for voice lineup construc-

tion, similar to the guidelines in use in many police

departments for eyewitness lineups. They advocate a

minimum of five voices in the lineup in addition to the

suspect, with foils being chosen for similarity to the

suspect’s sex, age, accent, socioeconomic background,

and vocal characteristics, such as pitch and speed of

speaking. They also recommend the use of double-

blind administrators and standardized instructions for

the earwitness—recommendations that are becoming

common in the realm of eyewitness procedure but need

stronger advocacy in the voice recognition arena.

Lori R. Van Wallendael

See alsoConfidence in Identifications; Estimator and System

Variables in Eyewitness Identification; Eyewitness

Identification: Field Studies; Eyewitness Memory;

Eyewitness Memory, Lay Beliefs About; Juries and

Eyewitnesses; Retention Interval and Eyewitness

Memory; Showups; Weapon Focus

854 ———Voice Recognition

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