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Making A Case

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Title: Making A Case


1
Making A Case
  • Interviewing Witnesses

2
Recognising Faces
Detecting Lies
Top-down Typology (FBI)
Factors Affecting Identification
Interrogation Techniques
Bottom-up Approach (Canter)
Cognitive Interview
False Confessions
Case Study (Railway Rapist)
3
Introduction Interviewing Witnesses
  • Within this topic there are three areas to
    consider
  • gt Recognising faces.gt Factors influencing
    identification.gt The cognitive interview.
  • Each of these areas has a research study to
    support the findings under the heading of
    interviewing witnesses.

4
Interviewing Witnesses
  • One key area for the police and to be able to
    make a case is the interviewing of witnesses who
    may have vital evidence to give. Research from
    the cognitive approach suggests that what a
    witness sees and remembers is influenced by many
    factors including
  • What might these factors include?

5
WHAT IS AN E-FIT?
Computerised method of synthesising images to
produce facial composites of wanted criminals
based on eyewitness descriptions
6
Who is this?
7
Recognising Faces
  • Recognising faces is a highly complex process
    that appears unique and fine-tuned in human
    beings.
  • The Thatcher Effect shows us that we are inclined
    to recognise upright faces.
  • These findings and others help us to understand
    the importance of accurate face recognition
    during the process of interviewing witnesses.

8
The Thatcher Effect
  • The Thatcher effect has shown that people are
    more likely to show recognition for the face
    which has upright distinct internal facial
    features.

9
Recognising Faces 35-36
  • Bruce and other researchers have shown that there
    is a clear difference between recognising
    familiar and unfamiliar faces.
  • Read the handout on Sinha et al (2006) research
    from a meta-analysis of face recognition
    research.
  • Match the 8 key factors on slide 9 that influence
    facial recognition.

10
Sinha et al. (2006) Summary of Face Recognition
research.
Low-resolution images
Facial reconstruction
Familiarity
Required for facial reconstruction
Faces processed as a whole (holistically)
Facial reconstruction is stationary
Eyebrows and hairline most important
CCTV images
Illumination influences recognition
Everyone has the ability to recognise faces
Motion of face helps recognition
Crimewatch TV programme
Special neurons developed for recognition
Facial reconstruction is expressionless
Faces and expressions are processed differently
Suspect seen in poor light
11
Background to Bruce et als study
  • Familiar faces enjoy high recognition even under
    difficult circumstances, whereas unfamiliar ones
    are often misidentified even in good conditions.
  • Familiar faces are recognised using their
    internal features (eyes, eyebrows, nose, mouth)

  • Whereas unfamiliar ones are recognised by
    external features such as head shape, hair and
    ears....
  • Witnesses tend to see suspects for a very short
    time and therefore use unfamiliar face perception
    when creating a composite.
  • This means that external features will be
    described best.
  • However, witnesses are trying to recognise
    familiar faces and therefore are relying on the
    internal features to identify them.

12
Internal and External Features
13
Evaluation of Recognising Faces Bruce et al
  • What was the sample?
  • What was the sampling method?
  • Can it be generalised?

14
Evaluation of Recognising Faces Bruce et al
  • What method was used in the study?
  • What are the strengths of this method?
  • What are the weaknesses of this method?
  • What is the advantage of using an independent
    design in this study?

15
Evaluation of Recognising Face Bruce et al
  • Comment on the reliability of memory in facial
    recognition?
  • Comment on the reliability of the study (think
    about doing two experiments)

16
PROBLEMS / ISSUES ASSOCIATED WITH FACE
RECOGNITION
  • Expectations / stereotypes (Duncan, 1976)
  • Limitations of technology
  • - exposure mode (static expressionless)
  • Errors in police procedure PG39

17
Factors influencing identification - Weapon
focusLoftus et al
  • What happens when a weapon is involved in the
    crime?
  • Weapon focus refers to the concentration of a
    witnesss attention on a weapon which results in
    them having difficulty in recalling other details
    of the scene identifying the person of the
    crime.

18
Weapon Focus
  • This is an estimator variable and is the idea
    that a witness will focus more closely on the
    weapon than they will on the person holding the
    weapon.
  • There is debate about the reason for this effect
    and whether it is caused by the danger posed by
    the weapon or the unusualness of the situation
  • Research into stress suggests that we perform
    poorly when we are at both high and low levels of
    arousal and best at a medium level of arousal
    ( Yerkes Dodson Law). This would suggest
    that a witness recall of crime would be poor
    when their level of physiological arousal is
    high. Attempts to test this hypothesis are
    affected by both ecological validity and ethical
    issues.

19
Evaluating factors influencing identification
Weapon focus Loftus et al
  • What method was used in the study?
  • What are the strengths of this method?
  • What are the weaknesses of this method?

20
Evaluating factors influencing identification
Weapon focus Loftus et al
  • Self-reports were also used in the study. What
    are the problems with this method?
  • Is eye fixation data a valid measure of someones
    attention to pieces of research?
  • Why is it effective to have a control group in
    this case?

21
Evaluating factors influencing identification
Weapon focus Loftus et al
  • What other factors besides the weapon could have
    caused the individual to forget what happened in
    the crime scene?
  • Comment on the reliability of the study (note
    two experiments were carried out).

22
The cognitive interviewFisher et al
  • The cognitive interview is a set of instructions
    given by the interviewer to the witness to
    reinstate the context of the original event and
    to search through memory by using a variety of
    retrieval methods
  • It rests on two basic assumptions
  • Memory of an event is made up of an
    interconnected network and that there should
    therefore be several ways of getting to the same
    point.
  • Retrieval from memory will be more effective if
    at the time of retrieval the context surrounding
    the original events can be reinstated.
  • Cognitive interviewing is designed to facilitate
    accurate recall through a set of instructions.

23
The Principles of CI Page 42
  • Interview Similarity
  • Focused retrieval
  • Extensive retrieval
  • Witness-compatible questioning

24
Fisher et al. Field Test of the Cognitive
Interview
  • Fisher and Geigelman
  • Found that if detectives were trained in CIT
    (cognitive interview technique, they found out
    significantly more information than those who
    were not trained.
  • It did take longer to conduct the interview, but
    the difference was not significant.

25
The cognitive interviewFisher et al
  • There are four basic principles, according to
    Fisher et al (1989). Explain each of them in a
    bit more detail
  • Interview similarity
  • Focused retrieval
  • Extensive retrieval
  • Witness-compatible questioning

26
Evaluating the cognitive interviewFisher et al
  • What could be a problem with the sample?
  • Which types of crimes will work best with the
    cognitive interview?
  • The CI depends on the witness being cooperative.
    Why?
  • What are some of the problems with the CI?
  • What do the police need to be careful about when
    carrying out the cognitive interview?

27
Overall Evaluating research into Interviewing
Witnesses
  • How are the studies reductionist?
  • Do the studies explain witness behaviour through
    personality or situational factors?
  • Is the research ethnocentric?

28
Evaluating research into Interviewing Witnesses
  • How can the research findings be applied to
    everyday life?
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