Truth and Deception Detection Psychology and the Law Truth and Deception Detection

Plan for Today Class experiment data Video Deception detection Interviewing

Manipulation Check Anxiety Scale Mean Std. Dev. F significance Control 20 34.45 8.697 14.574 .000 Anxi-ous 48.5 13.972 Total 40 41.47 13.512

Dependent Measure N Mean Std. Dev. F significance Control 20 8.2 3.259 4.217 .05 Anx-ious 5.8 2.267 Total 40 6.92 4.334

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 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 Statement Validity Assessment Helps to distinguish truthfulness of witnesses, particularly children in sexual abuse cases Open ended interview (taped) Criteria-Based Content Analysis 19 reality criteria (e.g., detail and context) 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 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