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PSYA1 COGNITIVE PSYCHOLOGY – UNIT 3 –
MEMORY IN EVERYDAY LIFE –
1. EYEWITNESS TESTIMONY 2. THE COGNITIVE INTERVIEW
Learning objectives
1.Understand what is meant by eyewitness testimony (EWT).
2.
Be aware of some of the factors that affect accuracy of EWT with reference to
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research.
3.
Understand the impact of misleading information on EWT.
4.
Discuss factors affecting EWT, including anxiety and age.
NOTE THAT YOU CAN BE ASKED SPECIFIC QUESTIONS ABOUT ANXIETY AND AGE
BECAUSE THE SPECIFICATION STATED ‘INCLUDING’.
Eyewitness testimony (EWT)
Eyewitness testimony is the evidence given in court or in police investigations by
someone who has witnessed a crime or accident.
One of the main factors affecting the accuracy of memory for an event seems to
be what happens after the event has taken place. The memories laid down seem
to be quite fragile and subject to distortion by post-event information. Loftus
(1992) called this ‘misinformation acceptance’ where people accept misleading
information after an event and absorb it into their memory.
There is a greater tendency to accept post-event information as the time
increases since the event happened. This has important implications for the ways
in which the police and lawyers question individuals in criminal investigations.
Loftus and her colleagues used an experimental technique where participants are
shown a film of an event such as a road traffic accident. They are then exposed to
some kind of post-event information (often in the form of leading questions) and
are then tested for their memory of the original event.
A leading question is phrased in such a way as to prompt a particular kind of
answer. ‘Was the man wearing a hat?’ is a straightforward question that gets a
yes or no response, but, ‘What colour was the man’s hat?’ implies that the man
was wearing a hat and may lead to a false memory of a hat that wasn’t actually
there.
PSYA1 COGNITIVE PSYCHOLOGY – UNIT 3 –
MEMORY IN EVERYDAY LIFE –
1. EYEWITNESS TESTIMONY 2. THE COGNITIVE INTERVIEW
1. Research by Loftus on post-event information and leading questions(1975)
Procedure
Loftus showed participants a film of events leading up to a car accident.
After they had seen the film participants were divided into a control group and an
experimental group.
The control group was asked questions consistent with what they had actually seen
– ‘How fast was the white sports car going when it passed the STOP sign?’
The experimental group was asked a question that included misleading information
– ‘How fast was the white sports car going when it passed the barn while travelling
along the country road?’ (There was no barn in the film)
All the participants were then asked more questions about the accident.
Findings
Experimental group
Control group
Conclusion
17% reported seeing the barn
3% reported seeing the barn
Some participants given the misleading post-event
information had actually absorbed this with their
original memory and now really believed they had
seen a barn.
Discussion of methodological issues in this experiment
Loftus used realistic material (film footage of a car accident).
However, the situation was still artificial because the participants were aware that they had
to pay attention and that they were taking part in an experiment. In a real-life eyewitness
testimony incident, they may not have paid such close attention and may not have been
prepared. This lacked ecological validity because the setting was not real life. Furthermore,
there may been demand characteristics.
When participants know they are taking part in an experiment they often pick up on cues
regarding what the researcher is looking for. This can affect the way they behave, either
because they try to please the researcher and help them out by behaving in a way which will
confirm the hypothesis or by deliberately going against it.
Loftus tried to ensure that participants gave genuine answers by offering a money reward to
participants if they could correctly recall details from a film of an accident, she found that
over 70% of the participants made an error on a crucial question in line with the misleading
information that had been fed to them (reference to a STOP or a YIELD sign). The offer of
money was designed to eliminate the effect of demand cues as it motivated participants to
be genuine in their answers and not just behave in a way that they thought the research was
looking for. The fact that participants still gave incorrect answers suggests that the original
memory really had been altered as a result of the misleading post-event information.
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PSYA1 COGNITIVE PSYCHOLOGY – UNIT 3 –
MEMORY IN EVERYDAY LIFE –
1. EYEWITNESS TESTIMONY 2. THE COGNITIVE INTERVIEW
2. Loftus and Zanni (1975)
Procedure
Participants were shown a brief clip of a car accident and then asked a series of
questions
Participants were asked:
CONDITION 1
CONDITION 2
Whether they had seen ‘a’ broken headlight
Whether they had seen ‘the’ broken headlight
There was no broken headlight in the film.
Findings
CONDITION 1
CONDITION 2
7% reported seeing a broken headlight
17% reported seeing a broken headlight
Conclusion
Leading post-event information can distort recall of eyewitnesses.
3. Loftus and Palmer (1974)
Procedure
Showed participants a film of a car accident and asked them a series of questions about
events leading up to the accident. One crucial question concerned the speed of the car
on impact.
‘How fast were the cars going when they hit each other?’
Other groups were asked the same question but the verb was changed in each case to
‘smashed’, ‘bumped’, ‘collided’ or ‘contacted’?
Findings
The verb used significantly affected speed estimates.
‘smashed’ produced the highest estimate of speed and ‘contacted produced the lowest.
A week later, when questioned again, participants who had been asked the ‘smashed’
version of the question were more likely to report having seen broken glass at the scene
of the accident, even though there had been none.
Conclusion
The way questions are posed in terms of the language used is very important as it can
distort recall.
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PSYA1 COGNITIVE PSYCHOLOGY – UNIT 3 –
MEMORY IN EVERYDAY LIFE –
1. EYEWITNESS TESTIMONY 2. THE COGNITIVE INTERVIEW
OTHER FACTORS AFFECTING EYEWITNESS TESTIMONY
1. ANXIETY
Loftus and Burns (1982)
Procedure
Some participants were shown a particularly violent version of a crime in which a boy
was shot in the face.
Findings
These participants had significantly impaired recall for events running up to the violent
incident.
Loftus (1979) – Weapon effect
Procedure
Participants were asked to sit outside a laboratory where they
thought they were hearing genuine exchanges between people inside the laboratory.
CONDITION 1
they heard an amicable discussion about an equipment failure. A man
with greasy hands then came out of the lab holding a pen.
CONDITION 2
they heard a hostile discussion, followed by the sound of breaking glass
and overturned furniture. A man then emerged from the lab holding a
knife covered in blood.
Participants were then given 50 photos and asked to identify the man who had come out of
the lab.
Findings
People who had witnessed the peaceful scene were more accurate in
recognising the man than the participants who had witnessed the more
violent scene.
Conclusion
The anxiety elicited by the weapon narrowed the focus of attention for
the witness so that they did not recognise his face so well.
Discussion
However, such laboratory studies might not reflect what happens in
real-life events. Even though it could be argued that this study tried to
make the incident seem real, the participants knew that they were due
to take part in an experiment of some kind and they may have guessed
that this was part of it. This may have meant that they were not as
anxious as they would have been in a real life setting (ecological
validity issues).
Survey
Findings
Christianson and Hubinette (1993)
110 people who had witness between them 22 bank robberies.
Some of these people had been bystanders in the bank while others
had been directly threatened by the robbers.
The victims (who had been subjected to the greatest anxiety) showed
more detailed and accurate recall than the onlookers.
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PSYA1 COGNITIVE PSYCHOLOGY – UNIT 3 –
MEMORY IN EVERYDAY LIFE –
1. EYEWITNESS TESTIMONY 2. THE COGNITIVE INTERVIEW
COMMENTARY
There is conflicting evidence about the effect of stress and anxiety on witness
recall. Laboratory-based studies have generally shown impaired recall in people
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who have witnessed particularly unpleasant or anxiety-inducing situations
whereas recall has been found to be very good after real life events. This makes
sense because the sympathetic arousal caused by acute stress enhances
memory.
METHODOLOGICAL ISSUES
Much of the research into EWT has been carried out in laboratory conditions.
The studies are well controlled, but participants are usually aware that they
are in an artificial situation and that their responses will not have serious
consequences for anybody.
Furthermore, in real life situations there are usually lots of things going on
at once which distract our attention. This may affect our ability to
accurately recall an event.
Anxiety levels may be higher in a real life situation especially when
witnessing a crime of some kind. It could be argued that taking part in an
experiment can also cause anxiety as the participant wants to do the right
thing and not be perceived as incapable or unintelligent. Anxiety can affect
recall negatively or positively depending on the level of it. It is difficult to be
sure if people’s memory is responding in the same way it would in a real
life situation for all of these reasons.
Foster et al. (1994)
Procedure
Participants watched a video of a bank robbery and were then asked to pick out
the robbers from an identity parade.
CONDITION 1 participants were told it was a genuine robbery and that their
responses would influence the trial.
CONDIITON 2 participants were led to believe that the fire was a simulation.
Findings
Participants were more accurate in condition 1 where they thought their testimony
would have real consequences.
Conclusion
PSYA1 COGNITIVE PSYCHOLOGY – UNIT 3 –
MEMORY IN EVERYDAY LIFE –
1. EYEWITNESS TESTIMONY 2. THE COGNITIVE INTERVIEW
EWT in real life might be rather different from those in experimental situations.
Recall might be more accurate when people think it really does matter.
2.
AGE (THIS IS ALSO NAMED ON THE
SPECIFICATION)
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NOTE THAT THERE IS A LOT OF RESEARCH ON THE
EFFECTS OF AGE ON EWT. BE FAMILIAR WITH ONE
ABOUT CHILDREN AND ONE ABOUT THE ELDERLY AS A
MINIMUM. BE SPECIFIC ABOUT AGES WHERE YOU CAN.
Witnesses are sometimes called upon to identify a criminal in an identity parade
and they are often reluctant to make a positive identification.
However, Dekle et al. (1996) found that children were more willing than adults to make a
positive identification but hey are often of the wrong person.
Children also seem to be more susceptible than adults to absorbing post-event
information into their original memory.
Poole
The parents of the children then read them a story, which contained some of the
elements of the science demonstration but also included new information.
The children were then questioned about the science demonstration.
Findings
They had incorporated much of the new information from the story into
their original memory.
Procedure 2
The children were asked to think carefully about where they had got
their information from (source monitoring).
Findings 2
Some of the older children revised their account of the science
demonstration and extracted the post-event information. The younger
children did not seem able to do this.
Conclusion
Younger children are poor at source monitoring (being able to identify
where their information came from. The testimony of young children
should be treated with caution.
Methodological issues
Although this was an experiment, it was harder to control extraneous variables in this
study as it was not in a highly controlled laboratory setting.
Investigators have to be particularly careful when using children so young as this to
make sure that they understand instructions and that they are paying attention.
As the children were with their parents in this experiment, they were less susceptible
investigator effects.
Flin et al. (1992)
PSYA1 COGNITIVE PSYCHOLOGY – UNIT 3 –
MEMORY IN EVERYDAY LIFE –
1. EYEWITNESS TESTIMONY 2. THE COGNITIVE INTERVIEW
Procedure
Findings
Conclusion
Children and adults were questioned one day after an incident
and then again five months later.
There were no differences in the amount and accuracy of
recall after a single day but there was significant forgetting in
the children after five months.
More forgetting takes place in children than adults over time.
This is an important implication because long delays often
occur between a crime being committed and subsequent court
proceedings.
Gordon et al. (2001)
Young children can provide details and accurate witness statements, but they are
particularly susceptible to suggestion and their accounts should be viewed with caution.
Davies (1994)
Davies believes that some of the differences between child and adult witnesses have
been overstated and that children can provide very valuable testimony provided care is
taken in the interviewing process.
Procedure
Findings
Procedure
Yarmey (1984)
An event was staged where an attacker had a knife.
80% of elderly (70yrs +) participants failed to mention that the
attacker had a knife in his hand. Only 20% of younger adults
(24 – 48yrs) failed to mention this.
Cohen and Faulkner (1989)
Showed a film of a kidnapping to groups of middle-aged and
elderly participants. They then read a narrative account of the
scene they had just witnessed.
For half the participants the narrative account was consistent
with the film
For the other half, the narrative contained some misleading
information.
Findings
Elderly participants were much more susceptible to the effects
of misleading information.
The cognitive interview
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PSYA1 COGNITIVE PSYCHOLOGY – UNIT 3 –
MEMORY IN EVERYDAY LIFE –
1. EYEWITNESS TESTIMONY 2. THE COGNITIVE INTERVIEW
LEARNING OBJECTIVES - YOU WILL BE ABLE TO:
1.
Describe the cognitive interview.
2.
Explain the rationale behind the cognitive interview.
If eyewitness testimony is inaccurate it can have serious and long-lasting
repercussions. For this reason, cognitive psychologists have tried to develop
methods for improving the accuracy of EWT. One suggestion is to improve the ways
in which witnesses are questioned by the police.
Geiselman et al. (1985) developed the cognitive interview technique in response to
research findings that the way eyewitnesses were questioned sometimes stifled
recall.
These techniques are designed to enhance retrieval of the original memory.
Although this kind of detail might seem trivial and poorly related to the actual
witnessed event, it is designed to provide extra cues that might help to jog witnesses’
memory for more central details.
The cognitive interview
Context reinstatement
Report everything
Instructions to witnesses
Mentally reinstate the context of the
target event.
Recall the scene, the weather, what you
were thinking and feeling at the time, the
preceding events, etc.
Report every detail you can recall even if
it seems trivial. ‘Tell me what you saw’.
‘Tell me what you heard’; ‘Tell me what
you smelt’. etc.
Recall from a changed perspective
Try to describe the episode as it would
have been seen from different
viewpoints, not just your own.
Recall in reverse order
Report the episode in several different
temporal orders moving backwards and
forwards in time.
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PSYA1 COGNITIVE PSYCHOLOGY – UNIT 3 –
MEMORY IN EVERYDAY LIFE –
1. EYEWITNESS TESTIMONY 2. THE COGNITIVE INTERVIEW
Geiselman et al. (1985) tested participants by showing them videos of a simulated
crime and then testing different groups with:
 a cognitive interview,
 a standard police interview
 an interview under the influence of hypnosis.
They found that the cognitive interview elicited more information from the
participants than either of the other two methods.
A number of subsequent studies have confirmed these findings although
Koehnken et al. (1999) found that witnesses questioned using the cognitive
interview also recalled more incorrect information than those questioned using
the standard technique. This is probably because the cognitive interview
procedure elicits more information overall than other procedures.
Fisher et al. (1990) have also demonstrated the effectiveness of the cognitive
interview technique in real police settings in Miami. They trained detectives to use
the enhanced cognitive interview techniques with genuine crime witnesses and
found that its use significantly increased the amount of information recalled.
Milne and Bull (2002) tested all the cognitive interview procedures. They found
that all four of the procedures used on their own produced more recall from
witnesses than standard interviewing techniques. However, the most effective
combination appeared to be the use of ‘Context Reinstatement ‘and ‘Recall
Everything’ instructions which is generally in line with the way the police tend to
use it.
The cognitive interview has not been very successful when questioning young
children. Geiselman (1999) reviewed a number of studies and concluded that
children under the age of six years reported events slightly less accurately in
response to the cognitive interview technique. This is probably because they find
the instructions difficult to understand. The technique can be used effectively
for children aged from about eight years upwards.
On balance, the cognitive interview technique has proved very useful
in increasing the amount and the accuracy of eyewitness statements.
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