Tuesday, January 29, 2013
PSYC 2400 - Winter 2013
Deception – Guest Lecture: Ian Broom, PhD
Intentional – create false belief in receiver
People lie (Hancock et al., 2004a)
• 14% e-mails
• 21% instant message
• 27% of face-to-face
• 37% of phone calls
Twice a day on average (DePaulo et al., 1996)
People are better at knowing when people are being truthful than when they are being deceptive
• Truth Bias
Crime leads to high-stakes lying
• Sentencing; parole hearings (remorse)
When there are high stakes, people lie better
Nature of deception
• Have to make up story
• Heart rate increases, sweating, shaking
How good are people at detecting deception?
Accumulated research literature suggests that people are not good at detecting deception.
The average person is accurate roughly 54% of the time when 50% would be expected by chance.
Deception can initiate a stress reaction
Activates the sympathetic nervous system
Cognitive element kicks in – aware of arousal
Control all perceived behavioural cues
Microexpressions more difficult to control (monitor)
• Time-reduced remnants of interrupted or inhibited facial muscular movements
Rigidity can emerge (e.g., Twyman, Elkins, Burgoon, 2011)
Honest – comfortable, open, and forward leaning posture
Deceptive – rigid, frozen, defensive posture
Can use movements to conceal other channels – which can give people away
Typical deceiver posture defensive
Leakage: Internal affective state of deceiver
Deception cues: Cues suggesting individual is trying to deceive you (e.g., finger tapping).
Liars and truth tellers should differ due to elevated arousal, cognitive load, and behavioural control.
Multi-tasking is taxing Non-Linguistic Cues
• No universal
• Look for mis-matches between content / messages and behaviour
• Non-linguistic verbal behaviour
• Rate of articulation
• Speech hesitations
• Response brevity
• Related to individual’s mental processing status
• There’s an APP for that!
• There are no independent research studies that support the use of VSA (NRC, 2003)
• Honest (and innocent) suspect, when questioned:
• tends to be helpful
• expects exoneration
• displays resentment towards the guilty party
• appears both spontaneous and sincere
• A deceptive (and guilty) suspect:
• provides less helpful information
• shows inappropriate concern about being a suspect
• lacks response spontaneity and sincerity
• uses both guarded and clearly edited verbal responses
• People are good at controlling themselves
• Good to rehearse your lie, but if you rehearse too much it’ll be obvious that you’re lying
William Moulton Marsten (May 9, 1893 – May 2, 1947) – created first polygraph and was also the created of
o Employee Screening : “…we have seen no indication of a clear and stable agreement on criteria for
judging answers to security screening polygraph questions in any agency using them.”(NRC,2003)
o Investigative Support: “The general quality of the evidence for judging polygraph validity is
• AntiPolygraph.org seeks the complete abolishment of polygraph "testing" from the American workplace.
Now that the National Academy of Sciences has conducted an exhaustive study and found polygraph
screening to be invalid, and even dangerous to national security, Congress should extend the protections
of the 1988 Employee Polygraph Protection Act to all Americans.
• The researcher who developed the U.S. Government's polygraph Test for Espionage and Sabotage
"thought the whole security screening program should be shut down?" • The National Academy of Sciences concluded that "[polygraph testing's] accuracy in distinguishing actual or
potential security violators from innocent test takers is insufficient to justify reliance on its use in employee
security screening in federal agencies?"
• ...spies are trained to pass the tests; polygraphs create a false sense of security; polygraphs drain
valuable resources from other effective and sound security measures; and polygraph tests
demoralize the staff, possibly jeopardizing the safety of information in such vital issues as nuclear
• Spies Ignatz Theodor Griebl, Karel Frantisek Koecher, Jiri Pasovsky, Larry Wu-tai Chin, Aldrich Hazen Ames,
Ana Belen Mon