susceptible to error and that witnessing variables, such
as emotions at the time of the event, can serve to affect
the accuracy rate. Around the same time, Hugo
Munsterberg released his book,On the Witness Stand,
which examined problems associated with eyewitness
memory as well as jurors’ inability to accurately
assess eyewitness testimony. Munsterberg’s research
was met with quick criticism from John Henry
Wigmore, who stated that psychological research was
not of a nature that the legal system could use. It is fair
to say that Munsterberg’s research was not up to pre-
sent-day methodological standards, but even with this
caveat, the importance of his work cannot be dimin-
ished. He was the first researcher to examine issues
related to eyewitness memory in a systematic and sci-
entific manner.
It was not until the 1970s that eyewitness research
was again brought to the forefront, this time by
Elizabeth Loftus. She demonstrated, using realistic
stimuli such as videotaped and live events, that memory
in general, including eyewitness memory, could be
altered simply by the way in which the interviewer
asked the question. Because of her rigorous method-
ological controls, she was able to both examine the
quantity of eyewitness memory and assess the accuracy
and quality of the remembered information. Her
research spurred interest in the topic among her
students and colleagues. This included Robert Buckhout,
who demonstrated the prevalence of eyewitness identi-
fication errors. Although there was still some skepti-
cism as to the use of eyewitness research in the legal
field, the research gained some ground in 1978, when
Gary Wells distinguished between estimator variables
and system variables. Establishing this dichotomy
made it possible for critics to comprehend how psycho-
logical research could contribute to the legal system
and allowed researchers to focus their efforts on issues
that the legal system could implement.Types of Eyewitness Memory and
Factors Affecting Eyewitness Memory
Broadly speaking, eyewitness memory can be divided
into two general classes: eyewitness recall and eyewit-
ness identification, corresponding to the traditional
recall-and-recognition distinction pervasive in the cog-
nitive psychological research on human memory.
Eyewitness recall often plays an important role in
the investigation of crimes. When a crime occurs,
police officers responding to the crime interview theeyewitnesses regarding their memories associated with
the crime, including descriptions of the perpetrator(s)
and the crime itself. The interviewee may be inter-
viewed numerous times throughout the investigation.
Some of the details recalled by the eyewitness, such as
a description of a weapon or description of clothing
worn by the perpetrator, may become important later
in the investigation or even at trial.
Research on eyewitness recall has examined
factors that influence the accuracy of eyewitness
descriptions, such as levels of stress experienced by
the eyewitness or the presence of a weapon. One of
the most widely studied factors, witness questioning,
relates to the information that is given to witnesses
after they experience the event and the way in which
the witnesses are questioned about the event. It has
been repeatedly demonstrated that the wording and
intonations of questions can lead eyewitnesses to pro-
vide incorrect information. In this research, partici-
pants who witnessed an event are questioned in a way
that induces subsequent reports containing false
details. For example, participant witnesses were
asked either “Did you see a broken headlight?” or
“Did you see the broken headlight?” Even though
only one word is different between the two condi-
tions, participants who heard the word “the,” rather
than the word “a,” were more likely to indicate that
they had seen a broken headlight. The majority of
research discussed thus far has involved adults.
However, research has also demonstrated sizeable
effects of postevent information on both older adults
and children alike. In fact, children below the age of
3 to 4 and adults over the age of 65 seem to be the
groups that are most likely to fall prey to postevent
suggestion.
Not only can memory of an event be altered by the
way in which the witness is questioned, but the act of
repeatedly questioning a witness can also have pro-
found effects on the witness’s memories of the event.
For example, repeatedly asking college students to
think about events that were plausible but did not
occur in their childhood (e.g., knocking over a punch
bowl at a party) led them to accept the events as true.
The most famous example is the “Lost in the Mall”
demonstration. In this demonstration, an adolescent
boy was asked to remember when he was lost in a
mall as a young boy. The boy, who initially indicated
he did not remember the event, was asked to simply
think about the event and write down his memories of
the event each night. This is a therapeutic techniqueEyewitness Memory——— 295E-Cutler (Encyc)-45463.qxd 11/18/2007 12:42 PM Page 295