Changing the way you learn

Making a Case

Interviewing Witnesses
1. Bruce et al: Recognising Faces
  1. Aim: to investigate the recognisability of internal (nose, eyes, brows, mouth) and external (head shape, hair, ears) in facial recognition.
  2. Lab experiment using an independent measures design involving 30 staff and students from Stirling University.
  3. Participants were given 10 pictures of celebrities and asked to match the correct composite image to the celebrity from 40 composites given. Group 1 were given complete composites, group 2 was given only external feature composites and group 3 were given only internal feature composities
  4. 42% of complete composites and external features were correctly matched to the celeb photo, compared to only 19.5% on internal features.
    1. External features are more important for facial recognition than internal features and faces are processed holistically.
2. Loftus et al: Factors affecting identification
  1. Aim: to provide support for the weapon focus effect when witnessing a crime.
  2. Lab experiment involving 36 students at the University of Washington, aged 18-31. Half were recruited through an advertisement and were paid $3.50 for their participation. The remainder participated in exchange for extra credit in their psychology classes.
  3. Participants were divided into two groups - the experimental group and the control group. They were both shown 18 slides of a queue in a Taco Time restaurant. In the control group person B (second person in the queue) handed the cashier a cheque. In the experimental condition, person B pulls out a gun. The dependent variable was measured by a 20-item multiple choice questionnaire. The participants were also given a line-up of 12 head and shoulder photos in a sequence and were asked to rate how confident they were of their identification on a scale of 1-6 (1= guess, 6= very sure). Researchers also used technology to measure eye fixation on the gun or cheque.
  4. 39.8% of people correctly identified the suspect in the cheque condition, compared to 11.1% in the gun. There was also a longer eye fixation time on the gun compared to the cheque,
    1. Participants spent longer looking at the gun and therefore had more difficulty identifying the suspect.
3. Fisher et al: Field test of the cognitive interview
  1. Aim: to test the cognitive interview (CI) in the field
    1. Four basic principles within the CI: 1. Event-interview similarity (psychological environment similar to the environment of the original event. 2. Focused retrieval (focused concentration = no interruptions and encouragement). 3. Extensive retrieval (make as many retrieval attempts as possible - imagining the scene from another viewpoint). 4. Witness-compatible questioning (interviewers should be flexible and alter their approach to meet the needs to each witness.
  2. 16 detectives from the Robbery Division of Dade Country, Florida. All with a minimum of 5 years experience within the division.
  3. All participants were asked to record a selection of their interviews using the standard interview technique. Then the group was split into two groups. The first group continued to use the standard interview technique, but the others were given four, one hour sessions training them in CI. They then implemented these techniques in their interviews.
  4. Police officers who were trained in the CI elicited 63% more information than the standard interview technique.
    1. Cognitive interview techniques seem to gain more information without losing accuracy.
Interviewing Suspects
1. Inbau et al: Reid's 'Nine Steps' Interrogation technique
  1. 1. Confront the suspect with their proposed guilt concerning the offence.
  2. 2. Offer the suspect the opportunity to shift blame (onto another).
  3. 3. Prevent/interrupt the suspect if they attempt to deny guilt.
  4. 4. Ignore denials, i.e. suspect's explanations of how/why they could not have committed the offence.
  5. 5. Maintain good eye contact, use suspect's first name, 'understand'/acknowledge suspect's difficulties.
  6. 6. When suspect becomes quiet, offer alternatives.
  7. 7. Offer two alternative explanations of guilt.
  8. 8. Ensure witnesses present when suspect admits guilt.
  9. 9. Ensure confession is written down and signed.
2. Mann et al: Detecting lies
  1. Aim: to test police officers ability to distinguish the truth and lies during interviews with suspects.
  2. Field experiment involving 99 police officers from Kent (75 males + 24 females) including 78 detectives.
  3. Police officers were shown 54 video clips of 14 suspects of real life police interviews. The clips were of head to torso range. They were asked... 1. truth or lie and 2. what cues helped you reach your decision?!
  4. It was found that police officers could accurately detect lies 66% of the time (better than chance). The most frequently mentioned cues were gaze, fidgeting and contradictions of the story.
    1. Police officers are better at detecting lies than chance and the best lie detectors relied on story cues are opposed to body cues
3. Gudjohnson et al: A case of false confessions
  1. Aim: to document a case of false confession of a youth who was at the time distressed and susceptible to interrogative pressure.
  2. 17 year old, of average intelligence, with no mental health issues.
  3. Case study of a youth accused of two murders (two elderly women were found battered to death in their home - their savings were missing and their were signs of sexual assault). FC was arrested due to inconsistencies with his movements and he was spending more money than usual. There was no forensic evidence - purely circumstantial. After he was arrested, he was denied access to a solicitor and was interviewed at length (14 hours during the night) by the police, leading to his confession. The next day he repeated his confession in front of a solicitor incriminating himself from jail.
    1. After a year in jail, he was released by a court after another person pleaded guilty to the crimes. This is a clear case of a coerced confession where suspects knowingly make a false confession in order to escape the stress of the interview.
Offender Profiling
1. Canter et al: Organised/disorganised theory of serial murder
  1. Aim: to investigate if there is empirical support for the organised/disorganised typology classification of serial killers .
  2. Participants: 100 cases of serial, sexual homicides committed by 100 US serial killers (known as Missen Corpus data).
  3. Method: Published Missen Corpus data cross-checked with court reports and, where possible, investigating officers. Content analysis (which identified 39 different crime 'factors') followed by multi-dimensional scaling test (SSA) of co-occurrence of 39 factors. Crimes followed Crime Classification Manual (CCM) in relation to crime scene and offender characteristics (third crime used).
  4. Twice as many disorganised as organised crime-scene actions were identified, suggesting that disorganised offenders are more common or alternatively, easier to identify. Only two crime-scene behaviours occurred in the organised typologies in a level of significantly above chance, which were that the body was concealed in 70% of cases and sexual activity in 75% of cases.
2. Canter et al: Developments in Offender profiling
  1. Aim: to identify behaviour patterns from similarities between offences.
  2. A content analysis was carried out on 66 sexual assault cases from various police forces. The data was subjected to Canter's smallest space analysis (a computer programme which uses analysis to find correlating patterns of behaviour).
  3. 5 variables were fond common to the 66 cases. 1. Vaginal intercourse. 2. No reaction to the victim. 3. Impersonal Language. 4. Surprise attack. 5. Victim's clothing disturbed.
  4. These are the most common features of rape, and as such they are not very useful for distinguishing between different types of rape crime scene,
3. Canter: The case of John Duffy
  1. Canter become involved in this case in 1985 when the police (convinced that a series of rapes/murders were the acts of one man) asked if he could help catch the man before he killed again.
  2. Aim: to systematically document crimes, crime scene details, chronology (subsequently geography) in order to infer possible behavioural characteristics of an offender, using psychological principles and scientific methods.
    1. Systematic data evaluation exercise in order to generate offender profiling. Data obtained from police data bases.
  3. Duffy was already on a police data base as he had been interviewed in connection with an attack on his ex-wife. He was also one of the nearly 2000 suspects linked to the crime by blood group. However, it was Canter's geographical profiling approach that was instrumental to his arrest. Duffy was the only suspect who lived in the Kilburn area of London, predicted as the home location of by Canter and exhibited other characteristics predicted by Canter.

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Making a Case

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	Created by elliebrett24 almost 11 years ago