test3- deception Flashcards
Cesare Lombroso (1885)
- first person to look at blood pressure with cuff to see if someone lying
- founder of movement that criminality could be bred out of species of humans
William Marston- pneumography
- Frye Criteria; advocated to have him testify with his lie detection device, ruled against (device not generally accepted in field)
- was a polygrapher; called himself father of numograph (however wasn’t actually inventor)
what does a numograph measure?
-primarily blood pressure
what does a Polygraph measure?
- measured many things (ANS response)
- skin conductance, heart rate, breathing rate
what were polygraphs primarily used for until the late 80s in the US?
- employee testing (on hiring or some point during employment to identify theft or drug use on the job)
- now illegal
- no longer allowed in court (still used in investigation)
common uses of polygraphs
- criminal investigation
- interrogation
- insurance
- employee testing (limited to specific investigations of job-related wrongdoing)
- screening (assess candidates reliability and loyalty)
- polygraph disclosure tests (uncover info about offenders past behavior)
what is the main element that varies when giving a polygraph ?
how the questions are provided/ how user is questioned
Name the three main polygraph techniques
- relevant/ irrelevant test
- comparison questions test (CQT)
- concealed information’s test (CIT)
Relevant/ irrelevant polygraph test
- most primitive, not used much
- ask irrelevant questions and compare response to relevant questions (know ground truth of irrelevant questions so can tell when lying)
- often used on Dr. Phil
Comparison Questions Test (polygraph)
- most common technique worldwide
- relevant, irrelevant, and control/comparison questions asked (repeated multiple times)
- comparison questions should be emotionally arousing and know ground truth of, usually don’t have reason to lie about, tailored to person, not about issue at hand
- includes pre-test interview where develop comparison questions, learn about background, and convince suspect of accuracy of test
- guilty assumed to respond more to relevant Qs, innocent more to irrelevant Qs
- don’t have to respond to questions but better if do
Concealed Information Test (polygraph)
- determine if suspect knows info about crime that only person who committed would know
- ask multiple choice questions, give them time to pick answer (better to answer as know they are listening)
- measure ANS response (skin conductance) to correct answer
- only works if remember details of crime and if salient details only known by perpetrator
- most popular in Japan and Israel
- not used a lot b/c need many questions for accuracy, hard to come up with them as must be very familiar with case, and not a lot of motivation by polygraphers to switch to diff technique
how are lab studies conducted to test polygraph accuracy?
- have people lie and tell truth and see if can tell
- advantage: experimenter knows ground truth
- disadvantage: limited application to real world (motivational differences)
how are field studies conducted to test polygraph accuracy?
- involve real-life situations, actual suspects and actual polygraph examinations
- compare original examiners to blind evaluators
- see where used, if person fund to be guilty and said guilty= success (PROBLEM: conviction doesn’t necessarily mean guilt)
- could look at cases where DNA evidence said they are guilty
- many use confessions to establish ground truth
what are two ways to establish ground truth?
- judicial
- confessions
* both have their own issues*
what did CQT lab and field studies discover?
- results do not suggest that polygraphs are very accurate (bust still better than guessing)
- bias towards false positives (say your lying when telling the truth)
what are some CQT countermeasures?
- physical: tongue biting, pressing toes to floor
- mental: counting backwards from 7
- Honts, Raskin, Kirchner (1994): showed success with both measures; something mentally taxing while answering can show success
- can also learn to escape deception if learn rationale underlying CQT
what did CIT lab and field studies discover?
- false positives low, but false negatives high
- goof at identifying innocent, not as much for guilty
- Ben, Shakhar & Elaad (2003): accuracy improved with motivation, 5 or more q’s and verbal response
- in field study, if add more autonomic measures, false neg rate went down a lot and false pos increased slightly
CIT countermeasures?
- ant-anxiety drugs (ex. diazepam) –> have found to be ineffective
- other measures not well studied
which polygraph type should police be more inclined to use and why?
CIT b/c lower false positive rate- ppl are innocent until proven guilty, and wouldn’t accuse as many people falsely
Patricj & lacuna (1989) ‘group contingency threat’ study
- in real life there are consequences for polygraphs
- got ppl to participate from corrections facility, told them there was a bonus for participating
- told to convince a person you are telling truth, if everyone succeeds, all get bonus, if you fail, no one gets and they get told it was you who failed (increases stakes)
- Results: no difference between psychopaths and those with APD, no difference between psychopaths and non
NRC 2003- review of polygraph evidence
- tried to come up with recommendation regarding the polygraph
- physiological responses measured by polygraph are not uniquely related to deception (happen for many reasons)
- theoretical rationale for CQT is weak (compare and relevant questions are weak)
- lab studies overestimate accuracy
- no field studies satisfy min criteria for quality study
- claims about polygraph today are same as those throughout history (claim high accuracy but rarely reflected in research)
polygraph admissibility in Canada
- not admissible in Canadian criminal court of law
- results first submitted as evidence in US court in Frye v. US, but denied to be admitted
R. v. Beland (1987)- polygraph admissibility case
- only evidence was testimony of accomplices (hinged on witness credibility)
- tried to introduce polygraph evidence; just re-established rules against oath helping (bolstering credibility) which you cant do
- issue= distraction, as may get into question of if polygraphers are valid experts instead of actual issue
- if polygraphers had no machine wouldn’t be allowed to testify
- if whole case hinges on credibility, maybe should be allowed?
‘mystique of science’ or ‘aura of infallibility’
- worry that juries are inordinately influenced by scientific backing of the polygraph
- bias may make polygraph less accurate
- research done to see if jurors really influenced, found to be spotty with little affect on jurors
- other things jurors make decision on, but if case hinges on believability, may have an effect
brain based methods to investigate deception (2)
- event related potential- P300
2. FMRI
Event related potential- P300
- brain based method to investigate deception
- measure shift in voltage at particular time after stimulus presented (directly measuring brain response)
- associated with surprise response (presented infrequently)
- resistant to manipulation
- not good evidence, but has been admitted into court
- Issues: noisy measure, must show many stimuli
FMRI
- brain based method to investigate deception
- measure cerebral blood flow
- maybe a lie entre in brain that activates when lying
- lie conditions produce greater activation in prefrontal and anterior cingulate regions compared to truth
- Issues: requires cooperative person (cant move), must listen/focus on instructions, cant run for too long (habituation signal issues), research based on averaging data across many participants (healthy individuals included), concerns that may influence jurors (scientific)
what specific behaviors may be effected by lying?
- facial temperature (tested with thermal cameras-not that accurate)
- voice stress analysis (pitch)
- tone of voice or vocal cues
- body movement (language)
- micro-expressions
what is the best technique when it comes to examining behaviors for lies?
- vocal cues/ the content of story
- give few details, less plausible, less engaging/ fluent, more nervous, less cooperative
- deceptions cues easier to pick up when liar is motivated or lie is embarrassing
accuracy of professional lie catchers?
- professionals= 55%, students=54% (no difference)
- people rely on behaviors that lack predictive validity
- most people have truth-bias
- only small differences between liars and truth tellers (few cues to rely on)
what are police trained with to detect deception?
REID technique/ behavioral analysis interview
Vrij, Mann & Fisher (2006)
- study that wanted to see what REID technique does in relation to telling if someone is lying
- students asked to tell a convincing story to interviewer
- had people rate, using BAI rating scale, 1 to 5, as guide (ex. liars wont make eye contact so no eye contact=1)
- RESULTS: technique biased towards saying someone is lying when telling truth
Behavioral analysis interview assumptions
- liars less helpful, unconcerned about being a suspect
- exhibit more nervous behaviors
- answer quickly to knowledge questions, sound less sincere
- motive questions cause liar to shit positions (be uncomfortable)
- more evasive about purpose of interview or name someone they believe is innocent
- less likely to admit a crime has taken place
- express less confidence in being exonerated, less likely to have informed loved one of the interview
name 3 communication types and if they are universal or not
- spoken and written language- not universal
- gestures- only one gesture is universal (pointing)
- facial expression- universal
hypothesises of facial expressions
- stemmed for social contamination or
2. are unique and universal
what are facial expressions?
- convey emotions
- universal
- difficult to completely supress
Dr. Paul Ekman
- military research in psych (allowed to help many people)
- studied Fore tribes in Papua New Guinea, used to test hypothesis of universal facial expressions- found that they were universal
- developed FACS
- expression and microexpression training
- consulting
Name the basic emotions (6) -developed by Ekman
- anger
- disgust
- happiness
- fear
- sadness
- surprise
- can be broken down into subcategories*
FACS- Ekman & Frisen
- facial action coding system for writing down expressions
- describes 10,000 possible facial expression, produced by 40 muscles
- found microexpressions
microexpressions
- transformative expression for brief millisecond
- may be genuine emotional expression when trying not to convey that emotion
- discovered by Ekman
deception detection theory
some people naturally good at reading microexpressions which in turn makes them good lie detectors
Porter & Brinke (2008) ‘reading inbetween the lies: identifying concealed and falsified emotions in universal facial expressions”
-tape people looking at images that are positive, negative or neutral
-people asked to either make
=simulated emotions (fake expression when looking at neutral photo)
=masked (fake an emotion to an emotional photo)
=neutralized (maintain neutral expression)
-recorded inconsistent emotional expression, microexpression, blink rates
-RESUTS: made inconsistent expressions, no complete microexpression (some partial), blink rate higher in genuine than neutral conditions
-overall, judgments were 60% accurate
Porter, Woodworth & Birt (2000)- investigation of federal parole officers to detect deception
- parole officers and students watch tapes of personal accounts of serious events (with feedback, without, or feedback + cue info)
- training given to officers; involved myth dissolution, info provision and practice judgment, feedback and knowledge testing
- RESULTS: if practice deception judgment with person with training, this improves peoples abilities
- can also just improve by going through tapes with feedback
what 2 dimensions do disorders of deception vary on?
- whether intentionally or consciously producing symptoms
2. whether motivation is internal or external
factitious disorder
- falsification of physical or psychological signs or symptoms, or induction of injury or disease
- deception behavior evident even in absence of obvious external rewards
- may be aware they are intentionally producing, but lack insight into underlying psychological motivations
Munchausen syndrome by proxy
- rare factitious disorder
- parent falsifies symptoms in child to gain attention or sympathy
Malingering
- intentional production of symptoms for external gain
- external motivations may include: punishment avoidance, drug seeking, military avoidance, financial gain, shelter
somatoform disorders
-often encourage physical tests and invasive procedures- malingering will not
malingering explanatory models (3)
- pathogenic: underlying mental disorder, little empirical support
- criminological: focuses on badness; a bad person (APD), in bad circumstances (legal difficulties), who is performing badly (uncooperative)- little empirical support
- adaptational: occurs when there is perceived adversarial context, personal stakes are high, and no other viable alternatives are perceived
defensive
=opposite of malingering, conscious denial or extreme minimalization of physical or psychological symptoms
how to study malingering?
- simulation design: ppl pretend to have specific symptom, used to address whether measure can detect malingering (disadvantage= limited generalizability)
- known group design: compare genuine patients with malingerers, analyze differences (difficulty with reliable and accurate classification of criterion group- used rarely)
instrumental psychosis
identify patients attempting to fake symptoms to secure special accommodations
how might someone tell if patient is malingering psychosis?
- overreact
- wiling to discuss symptoms
- more likely to report positive symptoms
- understandable motive for committing crimes
- suspicious hallucinations and delusions
- difference between interview and non-interview behavior
- sudden emergence of symptoms that explain crime
- no subtle sign of psychosis
assessment methods for malingering psychosis
- interview based method (SIRS)
2. Self-report questionnaires (MMIP-2):questions designed to detect ‘faking bad’
