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Eye Witness Testimony

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Title: Eye Witness Testimony


1
Eye Witness Testimony
  • EWT

2
Eye Witness Testimony -1
  • AO1 - outline what is meant by the terms EWT and
    Leading questions
  • A01/2 -Discuss the factors that affect the
    accuracy of EWT (leading questions, anxiety, age
    of witness)
  • Evaluate the impact of misleading information
    on EWT

3
Eyewitness Testimony
  • Reconstructive memory
  • Schema driven errors
  • Effect of leading questions
  • Other factors
  • Weapon focus
  • Effects of anxiety/arousal
  • Age of witness

www.psychlotron.org.uk
4
Reconstructive Memory
  • Bartlett (1932)
  • Memory is not a direct record of what was
    witnessed
  • What is encoded and how it is retrieved depends
    on
  • Information already stored in memory
  • How this info is understood, structured and
    organised

www.psychlotron.org.uk
5
Reconstructive Memory
  • Schemas
  • Knowledge structures that relate to commonly
    encountered objects, situations or people
  • Enable us to predict events, make sense of
    unfamiliar circumstances, organise our own
    behaviour
  • Act as filters to perception recall

www.psychlotron.org.uk
6
Computer Information Processing
BANG!
Can you wreck a nice beach?
www.psychlotron.org.uk
7
Schema Driven Processing
Yes. I can recognise speech.
www.psychlotron.org.uk
8
Bartlett (1932)
www.psychlotron.org.uk
Bartlett (1932)
See also Carmichael et al (32) p 32 Exploring
Psychology
9
EWT Schema Driven Errors
  • Witnesses to crimes filter information during
    acquisition recall
  • Their schematic understanding may influence how
    info is both stored retrieved
  • Distortions may occur without the witness
    realising

www.psychlotron.org.uk
10
EWT Schema Driven Errors
  • Past experiences
  • Assumptions about what usually happens
  • Stereotypes beliefs about crime criminals

www.psychlotron.org.uk
11
Look at this picture
12
  • Write down a description of what is happening in
    the picture

13
Factors that affect Eye Witness Testimony
  • Stereotypes - Allport and Postman (1947)
    Participants shown a cartoon of a black and a
    white man on a subway train. Most recalled that
    the black man had the razor in his hand. The
    razor was actually in the white mans hand.
    (stereotype more prone to violence).
  • Conclusion When an actual perceptual fact
    doesnt match our expectations, we trust our
    expectation more than the real situation.
  • We see what we expect to see and this forms the
    basis for the memory for an event.

14
EWT Leading Questions
  • Loftus (1970s onwards)
  • Effect of leading questions on recall
  • Leading questions introduce new information
  • Leading info may activate wrong schemas in
    witness mind
  • Consequently, witness may recall events
    incorrectly

www.psychlotron.org.uk
15
Factors that affect reconstructive memory
  • How witnesses are interviewed leading
    questions, facial techniques, tone of voice of
    interview may unintentionally communicate their
    expectations (what they want to hear).

16
Eye Witness Testimony
  • Elizabeth Loftus (70s) Research)
  • Illustrated the reconstructive nature of memory.
  • Star Study Loftus and Palmer (1974)

http//www.youtube.com/watch?v8hwEUaOeuFQ
17
The role of misleading questions?
  • In her research Loftus showed that memories can
    be affected by the wording of questions.
  • A leading question is a question about an event
    that is phrased in such a way as to prompt a
    particular answer.
  • Information is provided in the question (i.e.
    after the event) which may distort the accuracy
    of the memory.

18
Do people believe EWTs?
  • Loftus (1974) shows that people tend to believe a
    suspect is guilty if there is an eyewitness.
  • So it is very important that psychologists find
    out why EWT is inaccurate and how to improve
    accuracy.

19
Loftus and Palmer (74)
  • Read about this classic research in your text
    book
  • Draw a graph of the results
  • What conclusion can be drawn from this research?
  • What does is suggest about the accuracy of EWT?
  • Any problems with this piece of research?

20
EWT Leading Questions
  • Loftus studies using film/video/slides road
    accidents
  • How fast were cars going when they hit or
    when they smashed?
  • Smashed led to higher speed estimates
  • Loftus and Zanni (1975)
  • Did you see a/the broken headlight?
  • The produced more affirmative (incorrect)
    responses

www.psychlotron.org.uk
21
EWT Leading Questions
  • Loftus research usually lab based
  • Restricted samples (students)
  • Artificial stimuli (slides, videos, not real
    events)
  • Potential for demand characteristics to influence
    responses
  • No legal/moral consequences for inaccurate
    answers. (Foster et al (1994) witnesses more
    accurate in recalling memory of a bank robbery
    when they were led to believe their testimony
    would influence a real trial.)

www.psychlotron.org.uk
22
What other factors affect Eye Witness Testimony?
  • Anxiety

If you were a witness to a crime How would you
feel?
23
What other factors affect Eye Witness Testimony?
  • Age of witness
  • Can we rely on the testimony of children and
    older people?

24
How does anxiety and age of witness affect EWT?
Over to you..
  • You will be given one of the above to research
    using the text book.
  • Produce a bullet point summary
  • to report your findings back to the other group.

25
Anxiety Weapon Focus
  • When a weapon is used to threaten a victim, their
    attention is likely to focus on it
  • Consequently, their recall of other information
    is likely to be poor

www.psychlotron.org.uk
26
EWT Arousal Effects
  • Memory is most effective at moderate arousal
    levels
  • If the witness was in a state of extremely low or
    high arousal then recall may be poor

performance
arousal
www.psychlotron.org.uk
Graph to show the Yerkes-Dodson Law that says
that performance is best in moderately arousing
conditions
27
Yuille and Cutshall (86)
  • Assessed level of arousal and accuracy of
    testimonies from 13 witnesses to real robberies
    or murders.
  • Less accurate recall when levels of arousal were
    high than low, BUT very high arousal led to
    better recall than moderate.
  • Does not match Yerkes-Dodson Law
  • Could be explained by how close (proximity)
    witnesses were to the crime
  • Closest are more stressed, but have better view

28
Freud (1894)
  • Repression motivated forgetting
  • Traumatic memories become inaccessible (in
    unconscious) to protect us from being upset by
    them.
  • Conflicting evidence for this theory
  • See p 31 Exploring Psychology

29
Age of Witness and EWT
  • Children
  • Brennan and Brennan (88)
  • 6-15 year olds failed to understand 1/3 of
    questions asked by lawyers.
  • More correct answers when asked more simple
    questions (Carter et al 96)
  • Tags didnt she added at end led to more
    yes answers than when tag not there (Krackow and
    Lynn 03)

30
Age of Witness and EWT
  • Children
  • Children often change answers if question
    repeated. (Samuel and Bryant, 84. Blades and
    Krahenbuhl, 06)
  • Memon et al (06) positive, but not negative
    stereotypes affect childrens judgements about
    people.
  • Defendents with more positive stereotype less
    likely to considered guilty.

31
Age of Witness and EWT
  • Thinking Critically about psychology p 36
  • How does Memon et als research findings help to
    explain why Ian Huntley was able to get away with
    the crime for so long? When he was interviewed
    on TV at the time of the murder he wasnt
    considered a suspect

Ian Huntley (2003) Soham murders
32
Age of Witness and EWT
  • Older Adults as Witnesses
  • Assumption by police and society that Memory
    fails with age, so less reliable Eye witnesses.
  • Backed up by
  • (Holliday, 05), Brimacombe et al (97), Wright
    and Holliday (07)
  • Age of witness made no difference in cognitive
    interviews (next lesson!!)

33
Plenary
  • Answer the following questions
  • What type of experiments were those carried out
    by Loftus in the 70s?
  • What are the strengths and weaknesses of her
    research?
  • Find examples of ethical issues raised during EWT
    research. How could they be addressed?

34
Homework
  • Summarise the work you have covered today as
    bullet points of the main points or a mind map.
  • Include Definition of leading questions, EWT,
    weapon focus, Yerkes-Dodson Law
  • - The research of Loftus (1974), Loftus and
    Zanni and Yuille and Cutshall (pros and cons,
    ethics e.t.c)
  • - the affect of leading questions, age and
    anxiety on EWT
  • Finish the Case of Wrongful Conviction activity
  • What does this task highlight about the impact of
    misleading info, age and anxiety on EWT?

35
Eye Witness Testimony -
  • AO1 - Describe the cognitive interview technique
    and understand its rationale
  • A01/2 - Describe and evaluate evidence that
    underpins our understanding of EW
  • AO2 - Discuss the impact of misleading
    information on EWT

36
The Cognitive Interview
  • In the light of the work of Loftus on the
    importance of Leading Questions in the 70s
    Police needed to change questioning techniques.

37
The Cognitive Interview
  • Also EWT typically takes place in a different
    context to acquisition (scene of the crime)
  • Lack of retrieval cues (state and context) can
    inhibit recall
  • Reconstruction of the events (either imagination
    or simulation) can lead to enhanced recall
  • This is one of the elements of the Cognitive
    Interview

38
The Cognitive Interview
  • Geiselman et al (1985) identified 4 key
    principles for the cognitive interview.
  • In pairs use p 37 of Exploring Psychology and p14
    of your revision guide to find out what those 4
    key principles are, plus the principles of the
    Enhanced CI (Fisher et a, 87)
  • Each study 4 and report back to your partner.
  • Fill in the worksheet, use as a revision tool.

39
The Cognitive Interview
  • Try it for yourself.
  • Work in fours 2 of you will be the interviewers
    and the other 2 the witnesses
  • Use the incident from the video
  • Either ask direct interrogative questions (see
    sheet)
  • Or Use a Cognitive interview technique (see
    sheet)
  • Compare the accuracy of the recall.

40
The Cognitive Interview
  • Outline the pros and cons of the CI, using
    research studies
  • Fisher et al (87)
  • Geiselman (86)
  • Geiselman and Fisher (97)

41
The Cognitive Interview
  • Pros lots of studies (in real and lab
    situations) have shown that CI produce more
    forensically rich information .
  • Cons Can be time consuming some elements
    missed out (Thames Valley Police)
  • - Insufficient training (Memon et al 94)

42
Plenary
Think LoP
  • Create a poster, leaflet, or mind map of what you
    have learnt about what factors can affect Eye
    Witness Testimony and recommendations for how
    best to make EWT testimonies as accurate as
    possible.
  • Think about your audience. Select the most
    important points. Have a balanced view.
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