CHAP 4 (Deception) Flashcards
Historically, belief that criminals can be caught by physical manifestations of their denials
Suspects in India once required to submit to “trial by sacred ass” (500 BC)
Mud put on tail of donkey in a tent
Required to enter tent and pull tail, innocent if donkey doesn’t bray
But actually had to do with whether or not the person had dirt on their hands (whether they were too scared to touch donkey or not)
Hindus forced suspects to chew rice and spit it out on leaf from an ancient tree
If the rice was dry, the person is guilty
Bedouins of Arabia required conflicting witnesses to lick a hot iron
One whose tongue was burned was lying
What do the two examples of old physical deception both with rice and hot iron on tongue reflect?
Sympathetic nervous system
- Salivation decreases when stressed
Stress levels and emotion aren’t always ________ to lying
completely causal to lying
Developed in 1917 by William Marston
Called it the “lie detector”
Noting increases in systolic blood pressure when person lies
“Made Wonder Woman”
Polygraph
Polygraph measures _______, and in the body measures __________
It measures emotions, not “lying”
May or may not be related
“Poly” multiple measures
Measures blood pressure, heart rate, breathing rate, galvanic skin response, etc
Anything Better? Than Polygraph
Concealed Information Test / Guilty Knowledge (Lykken, 1981)
- Goal is to detect presence of guilty knowledge in person’s mind, not lying
- Relies on accumulation of facts known only by police, criminal, surviving victims
- “In what room was the body found?” / “What was the murder weapon”
Concealed Information Test / Guilty Knowledge (Lykken, 1981)
Start with the baseline “lie” (have you ever told a lie?)
Other responses can be compared to it
Comparison Question / Control Question (Reid 1947)
Polygraph Conclusions
Can be very useful to get suspect to confess
A “confession inducing” technique (similar to the REID)
- Not the machine, but suspect’s beliefs DECIDE WHO IS GUILTY
Rapport is key
Brain Scan Techniques of Deception
FLAWS?????
Brain Fingerprinting (guilty knowledge with technology by measuring brain fMRI)
“Brain Wave Science” (ERP Research; p300 amplitude)
fMRI Research (Langleben 2001)
18 men. Sizable activity in some areas when lying about cards
IMPOSSIBLE TO IMPLEMENT DUE TO COSTS AND TIME NEEDED
18 MEN ALONE TOOK MONTHS JUST TO TELL THEY WERE LYING ABOUT CARDS
Nonverbal Communication in Deception
Idea is that non verbal “leakages” are harder to conceal
Facial Expressions (shortly)
E.g; decreases in limb movements are believe to be indicative of deception
Non-Verbal Cues:
Never used as evidence in court
Still useful (e.g customs inspector)
For mixed messages
Non-verbal usually better indicator (harder to control)
List from OPP
Nodding, foot and hand movements (maybe)
Pretty much all forms of Nonverbal Communication cues to decept decpetion are ___________________
Never used as evidence in court
Polygraphs are not allowed in the use of _____ in Canada or the US
Courts
Approaches to using ANY deception cues in court
Using this evidence in court
U.S Rules of evidence (and Canada R v Mohan)
Frye (1923) “general acceptance” rule
Replaced Frye WITH Daubert (1993)
“ A conclusion will qualify as scientific knowledge if the proponent can demonstrate that it is the product of sound “scientific methodology” derived from the scientific method”
Up to judges to decide what is “valid science”
Comes down to the “common sense” idea and invading the purview of the jury
Paul 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)
In Paul Eckmans research, the Brokaw Hazard
- named after Tom Brokaw
- After tons of years, he believed he was incredibly good at detecting lies
- “Convoluted answers or sophisticated evasions” - Ignores individual differences in how people respond
- Brokaws idea are unfounded
- “Convoluted answers or sophisticated evasions” that are supposed to catch deception but Ignores individual differences in how people respond is the
the Brokaw Hazard
Observing ways in which physiological responses are inconsistent with verbal accounting
The Leakage Hypothesis
Behavioural Analysis in Deception
Analysis of “micro-expressions” (largely based on Eckmans work)
Other “Techniques”
Eye movement and Neuro Linguistic Programming
No evidence for any of this
Voice Analysis
Spectrogram - Voiceprint analysis
Voice stress and “micro-tremors” in speech pattern
Deception is correlated (SOMETIMES) with more speech disturbances, slower rate of speech, higher pitched voice, longer latency to answer (but not always!)
Cognitive Load (Vrij)
Easier to know when someone is truthful
Difficult lies take cognitive resources (so easier to detect)
But simple lies have different patterns
Not legally accepted or scientifically established
falsification or profound exaggeration of illness (physical or mental) for a specific reason
Malingering
a mother with a child that is very sick or has an ailment, just when they get home and out they go back immediately, this will give doctors an assumption that the parent is purposely poisoning the child.
or ie they will pretend they themselves are sick
SPECIFICALLY REGARDS MEANING OR ATTENTION / BENEFITSFROM ACTION
Munchausen / Proxy
- proxy ONLY IF FAKING ANOTHERS HEALTH NOT THEIR OWN
Rosenhan (1973)
“On being sane in insane places”
8 Sane individuals went to 12 different hospitals (5 States)
All said that they had been hearing voices, and that the voices said “empty, hollow, thud”, other than this they gave no other deceitful statements (real life histories presented)
As soon as they were admitted, argued that all “symptoms” were gone
Wanted to see how long before they were detected of being fake patients, they never were
All but one admitted for “schizophrenia”, all released with “schizophrenia in remission”. Were in the hospital for 7-52 days (19 Days on Average)
Yet real patients (35/118) figured out that they were faking
How good are we at detecting deception?
Okay but hardly foolproof
Efficacy versus validity is a big issue (thinking your good at is different than being - Confirmation Bias)
Just a tool?????
