b6 - eyewitness testimony Flashcards
what is eyewitness testimony?
is the ability of people to remember the details of events which they themselves have observed
what are the two main factors that effect EWT?
misleading information
anxiety
what is misleading information?
incorrect information given to an eyewitness usually after the event
what are the two forms of misleading information?
leading questions
post event discussion
what are leading questions?
a question which, because of the way it’s phrased, suggests a certain answer
name a study of leading questions
Loftus and Palmer (1974)
explain Loftus and Palmers study on leadings questions - first experiment
45 students shown a 7 film clips of traffic accidents,
students had to answer some specific questions and a critical question (speed of the vehicle involved in accident),
5 conditions, key word was changed in each conditions:
“how fast were the cars going when they ___ into each other”
c1: smashed
c2: collided
c3: bumped
c4: hit
c5: contacted
results:
smashed = 40.8mph (fastest speed estimated)
contacted = 31.8mph (slowest speed)
what are the two explanations of why leading questions affect EWT?
the response bias explanation,
the substitution explanation
explain the response bias explanation of leading questions
the wording of the question has no real effect on ppts memories, but influences how they decide to answer
what is post-event discussion?
occurs when there is more than one witness to an event. whiteness discuss what they have seen
name a study of post event discussion
Gabbert et al (2003)
explain Gabbert et al’s study on post event discussion
procedure:
ppts put in pairs and each shown footage of the same crime but from different view points,
after they discussed what they saw
findings:
71% mistakenly recalled aspects of the event they didn’t see but had picked up in the post event discussion.
control group: 0% mistakenly recalled with no discussion.
witnesses confirm for social approval
one strength of misleading information
real life allocations - how police questioning are phrased
two limitations of misleading information
studies use artificial material- no emotion
individual differences - people are more accurate at recalling details of a crime when the suspect is similar to themselves
explain the substitution explanation of leading questions
the wording of leading questions actually changes the ppts memory
how does anxiety effect the accuracy of EWT?
negative effect on recall,
create physiological arousal in the body which prevents us paying attention to important cues
what does the presence of weapons have an an individual?
weapon focus - negative effect on EWT
name two studies of anxiety on EWT
Johnson and Scott (1976)
Guillermo and Cutshall (1986)
explain Johnson and Scott’s study on anxiety on EWT
procedure:
led ppts to believe they were going to take part in a lab experiment.
whilst waiting they heard an argument in the next room
c1: low anxiety: a man walked through the area with a pen and grease on his hands
c2: high anxiety: sound of glass breaking and a man walked through with a pen knife and blood on hands
they had to pick the out the man from a set of 50 photos
findings: 49% c1 could identify the man vs 33% c2
what conclusion was made for Johnson and Scott’s study of anxiety on EWT
tunnel theory- attention becomes narrowed and focuses on the weapon as a source of anxiety
one limitations of Johnson and Scott’s study
people may focus on the weapon because they are suprised not because of anxiety
explain Yuille and Cutshall’s study on anxiety on EWT
procedure:
real life study on shooting in Vancouver, 13 whitnesses took part.
interviews 4-5 months later
findings were compared with interviews by police that took part at the time of the event.
accuracy determine by how many details remembered.
rated their stress on 7-point scale.
findings:
accuracy hadn’t changed in 5 months
those who reported most stress were most accurate
two limitation of anxiety on EWT
field studies lack control
ethical issues - creating anxiety (harm)
who created the inverted U theory?
Heroes and Doson (1908)
what conclusions were made from Yuille and Cutshall’s study of anxiety on EWT
anxiety can enhance alertness accuracy and memory
what is the inverted U theory?
the relationship between emotional arousal and performance looks like an inverted U,
lower levels of anxiety increase accuracy, once anxiety goes over the optimal point accuracy decreases
what technique is used to improve EWT?
the Cognitive interview technique
what is the cognitive interview technique?
a method of interviewing eyewitnesses to help them retrieve more accurate memories.
who designed the cognitive interview?
Fisher and Geislman (1992)
what are the four main components of the cognitive interview?
report everything,
context reinstatement,
recall in reverse order,
recall from a different perspective
explain ‘report everything’ in the cognitive interview and why might it improve recall?
witnesses recall all details that they can remember regardless of how trivial they appear.
might highlight something that has been overlooked
explain ‘context reinstatement’ in the cognitive interview and why might it improve recall?
recreat the sene in the mid of the whiteness (signs, smells, sounds, emotions) - cues
cues may trigger recall
explain ‘recall in reverse order’ in the cognitive interview and why might it improve recall?
recall events in different orders.
verifies accuracy and reduces possible that recall is influenced by schema/expectations
explain ‘recall from a different perspective’ in the cognitive interview and why might it improve recall?
access sense from another’s point of view.
promotes a more holistic view of the event which may enhance recall and reduce influence of schema.
name two studies of the cognitive interview
Kohnken et al (1999)
Milne and Bull (2002)
explain Kohnken et al’s study for cognitive interview
carried out a meta-analysis of 53 other studies and found that the CI could elicit 34% more detail than standard interviews
explain Milne and Bull’s study for the cognitive interview
found if one of the four components of the CI are used individuals, there’s not much difference to standard interviews.
but when two or more components are used there is significant recall improvement
two strengths of the cognitive interview
used in police interviews,
many studies support
two limitations of the cognitive interview
time consuming to train interviewers,
increases the amount of correct and incorrect information
what must police not do when conducting a cognitive interview?
interrupt the witness
