Transcript Abnormal Psychology

Psychology and the Law
Truth and Deception Detection
Plan for Today
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Class experiment data
Video
Deception detection
Interviewing
Manipulation Check
Anxiety Scale
N
Mean
Control 20
34.45
Std.
Dev.
8.697
Anxious
20
48.5
13.972
Total
40
41.47
13.512
F
signific
ance
14.574 .000
Dependent Measure
N
Mean
Control 20
8.2
Std.
Dev.
3.259
Anxious
20
5.8
2.267
Total
40
6.92
4.334
F
signific
ance
4.217
.05
Lie Detection
• Eckman (1985) Telling Lies
“lying is when one person intends to mislead
another, doing so deliberately, without prior
notification of this purpose, and without having
been explicitly asked to do so (p. 28)”
“Brokaw hazard”
The Leakage hypothesis – can detect deception by
observing ways in which physiological responses
are inconsistent with verbal accounting
Lie Detection
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Polygraph
Statement Analysis – (SVA , CBCA)
Behavior Analysis
facial expressions
Eye movement and Neurolinguistic programming
Eye contact
Body movement
Voice
Brain scan
Polygraph
• Truthfulness is more dependent on
situational contexts than on a general trait of
honesty
• Based on autonomic arousal system
• S.C.C. (1987) ruled polygraph inadmissable
Statement Analysis
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Statement Validity Assessment
Helps to distinguish truthfulness of witnesses,
particularly children in sexual abuse cases
1) Open ended interview (taped)
2) Criteria-Based Content Analysis
19 reality criteria (e.g., detail and context)
3) Validity checklist (e.g., age appropriate
language, motivations)
Voice Analysis
• Spectrogram - voiceprint analysis
• Voice stress and micro-tremors in speech
pattern
• Deception is correlated with more speech
disturbances, slower rate of speech, higher
pitched voice, longer latency to answer
• Not legally accepted or scientifically
established
Non-Verbal Behavior
• Non verbal leakages are harder to conceal
• Facial expressions don’t match the context
• Decreases in limb movements are indicative
of deception
New Measures of Deception
• Brain Scan
• Memory Scan
• Facial Blood-flow
Police Interviews
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With witnesses vs. suspects
Memory enhancement procedures – e.g., Guided
Memory Technique, Structured Interview
Cognitive Interview (Enhanced)
Guided imagery
Temporal order
Report any related matter
Recall using different perspectives
Interviews with Suspects
• 80% of criminal cases solved by confession
• False confessions account for the most
wrongful convictions next to eyewitness
misidentification
• Torture vs. Soft cell
• brainwashing
False Confessions
• Voluntary false confession
– protection, reward, alibi, fear, fame
• Coerced-Compliant false confession
– escape or reward (instrumental reasons)
• Coerced-Internalized false confession
- creation of false memories