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Making A Case
Interviewing Witnesses
Recognising FacesRecognising Faces
Factors Affecting Factors Affecting IdentificationIdentification
Factors Affecting Factors Affecting IdentificationIdentification
Cognitive InterviewCognitive InterviewCognitive InterviewCognitive Interview
Detecting LiesDetecting LiesDetecting LiesDetecting Lies
InterrogationInterrogationTechniquesTechniques
InterrogationInterrogationTechniquesTechniques
False ConfessionsFalse ConfessionsFalse ConfessionsFalse Confessions
Top-downTop-downTypology (FBI)Typology (FBI)
Top-downTop-downTypology (FBI)Typology (FBI)
Bottom-upBottom-upApproach (Canter)Approach (Canter)
Bottom-upBottom-upApproach (Canter)Approach (Canter)
Case StudyCase Study(Railway Rapist)(Railway Rapist)
Case StudyCase Study(Railway Rapist)(Railway Rapist)
Introduction: Interviewing Witnesses
• Within this topic there are three areas to consider:
> Recognising faces.> Factors influencing identification.> The cognitive interview.
• Each of these areas has a research study to support the findings under the heading of 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?
Interviewing Witnesses
WHAT IS AN E-FIT?
Computerised method of synthesising images to produce facial composites of wanted criminals based on
eyewitness descriptions
Who is this?
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.
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.
•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.
Recognising Faces: 35-36
Sinha et al. (2006) Summary of Face Recognition research.
Illumination influences recognition
Motion of face helps recognition
Special neurons developed for recognition
Familiarity
Faces processed as a whole (holistically)
Eyebrows and hairline = most important
Low-resolution images
Faces and expressions are processed differently
Everyone has the ability to recognise faces
“Crimewatch” TV programme
Facial reconstruction is expressionless
Required for facial reconstruction
Facial reconstruction is stationary
CCTV images
Facial reconstruction
Suspect seen in poor light
Background to Bruce et al’s 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.
Internal and External Features
PROBLEMS / ISSUES ASSOCIATED WITH FACE RECOGNITION
Expectations / stereotypes (Duncan, 1976)
Limitations of technology
- exposure mode (static; expressionless)
* Errors in police procedure PG39
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 witness’s attention on a weapon which results in them having difficulty in recalling other details of the scene & identifying the person of the crime.
• 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.
Weapon Focus
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.
The Principles of CI: Page 42
• Interview Similarity
• Focused retrieval
• Extensive retrieval
• Witness-compatible questioning
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.
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: