Encyclopedia of Psychology and Law

accuracy rates by forcing participants to make a fast

identification were unsuccessful. Thus, it appears that

the relatively short latency of accurate witnesses is the

result, not the cause, of the decisions processes that

produce accurate decisions. The other involved the

suggested use of a specific time (i.e., 10–12 seconds)

as the cutoff for distinguishing fast (i.e., reported in

less than 10–12 seconds), and consequently accurate

identifications, from slow (i.e., reported after more

than 10–12 seconds) identifications, which were less

likely to be correct. Despite the apparent early success

of this rigid rule, subsequent studies demonstrated

that the boundary between fast and slow decisions is

not constant but varies from situation to situation as a

result of changes in variables such as the target and

lineup, the nominal size of (i.e., the number of mem-

bers in) the photo array, and the retention interval

between viewing the offender and attempting to make

an identification from the lineup. The demonstrated

instability of the border that separates fast from other

identifications rules out the practical use of a univer-

sal response latency boundary to discriminate identifi-

cations with a high probability of being correct.

However, subsequent analyses using this type of static

response latency boundary (i.e., 10 seconds) in combi-

nation with a confidence criterion (e.g., identifications

made with 90% or 100% confidence) have shown

some promise. Although few decisions met both the

response latency and confidence criteria, those deci-

sions observed a very high accuracy rate across a num-

ber of stimuli and viewing conditions. Consequently,

the most encouraging use for response latency appears

to be in combination with other markers of identifica-

tion accuracy—most notably confidence.

Response latency is often inappropriately referred to

as decision latency (or decision speed). Although this

may seem a pedantic, semantic distinction it under-

scores an important point about the measurement and

use of response latency in the eyewitness identification

domain. Specifically, an eyewitness, particularly a con-

scientious eyewitness, may not make a response imme-

diately on arriving at a decision. For example, the

attention of one witness with an excellent memory for

the offender may be drawn to a specific lineup member

as soon as he or she sets eyes on a photo array, and the

witness could feel certain that the perpetrator has been

found. However, to ensure that they have not made a

mistake, these conscientious witnesses may continue to

carefully examine each of the other lineup members

before identifying the lineup member to whom their

attention was initially drawn as the offender. In

contrast, the attention of another witness with a rela-

tively impoverished memory may not be drawn to any

specific member of the lineup. Consequently, that wit-

ness may conduct a careful and deliberate examination

of the lineup before making and indicating their identi-

fication decision. In other words, the observed response

latency may be affected by factors other than the

amount of time it took the witness to arrive at a decision

(e.g., their conscientiousness or their confidence in

their ability to make the correct decision).

At present, despite the consistent relationship

between latency and identification accuracy, these

findings do not lead to any practically useful methods

for reliably discriminating correct from incorrect deci-

sions, but the combined use of response latency with

confidence judgments appears to be a potentially

fruitful area of investigation.

Nathan Weber and Neil Brewer

See alsoConfidence in Identifications; Popout Effect in

Eyewitness Identification

Further Readings

Brewer, N., Caon, A., Todd, C., & Weber, N. (2006).

Eyewitness identification accuracy and response latency.

Law and Human Behavior, 30,31–50.

Dunning, D., & Perretta, S. (2002). Automaticity and

eyewitness accuracy: A 10- to 12-s rule for distinguishing

accurate from inaccurate positive identifications. Journal

of Applied Psychology, 87,951–962.

Sporer, S. L. (1993). Eyewitness identification accuracy,

confidence, and decision times in simultaneous and

sequential lineups. Journal of Applied Psychology,

78,22–33.

Weber, N., Brewer, N., Wells, G. L., Semmler, C., & Keast,

A. (2004). Eyewitness identification and response latency:

The unruly 10–12 s rule. Journal of Experimental

Psychology: Applied, 10,139–147.

RETENTIONINTERVAL AND

EYEWITNESSMEMORY

Retention interval refers to the amount of time that

elapses between the end of a witness’s encounter with

a perpetrator and any subsequent testing of the wit-

ness’s memory for that encounter. Testing of a witness’s

memory for a perpetrator’s identity is obviously impor-

tant whenever the prosecution seeks to prove that the

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