PSCY 2400C - Reading Notes (ch. 4 - 7, 11) PDF

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Ch. 4: Deception (pg. 94 - 125) how do we know whether someone is telling the truth or lying? several techniques have been developed to try to answer this question As seen in Chapter 3, police attempt to detect whether some- one is telling them the truth during an interrogation Psychologists have pa...

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Ch. 4: Deception (pg. 94 - 125)

- how do we know whether someone is telling the truth or lying? - several techniques have been developed to try to answer this question - As seen in Chapter 3, police attempt to detect whether some- one is telling them the truth during an interrogation - Psychologists have participated in the development and testing of a variety of techniques to detect deception - issues associated with deception: the use of the polygraph and alternatives to the polygraph, the relationship between verbal and nonverbal cues to deception, and methods for detecting the malingering (exaggeration) of mental disorders THE POLYGRAPH TECHNIQUE - psychological measures have long been used in an attempt to detect deception - Polygraph relies on the same underlying principle: Deception is associated with physiological change - The origins of modern polygraphy date from 1917 when William Marston, a Harvard psychologist also trained as a lawyer, developed a systolic blood pressure test (Iacono & Patrick, 1999) and attempted to use this physiological response as evidence for a person’s innocence - Marston’s testimony was rejected by the courts in Frye v. United States (1923) because they felt the test had not gained acceptance by the scientific community - A polygraph, the word is a combination of two Greek words, poly = “many” and grapho = “write” - a polygraph is a device for recording an individual’s autonomic nervous system responses - measurement devices are attached to the upper chest and abdomen to measure breathing - the amount of sweat on the skin is measured by attaching electrodes to the fingertips (skin conductance response) - heart rate is measured by a partially inflated blood pressure cuff attached to the arm - each measure is amplified and stored on a computer to be analyzed - in a forensic context, a polygraph is used to measure a person’s physiological responses to questions asked by an examiner.

- In Canada, polygraph training is provided by the Canadian Police College - The polygraph course at the Canadian Police College is restricted to police officers. The college offers a 12-week intensive course that covers the various techniques, inter- viewing practices, and scoring. APPLICATIONS OF THE POLYGRAPH TEST - polygraph test are used for a range of purposes - in Canada the police often use them to help in their criminal investigations - if a suspect fails a polygraph test, the person may be pressured to confess, thereby giving the police incriminating evidence - police may ask alleged victims of crimes to take a polygraph test to help verify whether a crime has occurred (not very common) - More recently, the polygraph has been used in the United States to assess and moni- tor sexual offenders on probation - Polygraph disclosure tests are used to uncover information about an offender’s past behaviour. - Some sexual offender treatment programs require sexual offenders to take a polygraph to help uncover undetected offences - In addition, polygraph tests have been used to determine whether the offender is violating the conditions of probation or to test for evidence of risky behaviour - polygraph test were used to screen employees for theft and drug use but the Employee Polygraph Protection Act of 1988 restricted private companies from using the polygraph for these purposes and limited the use of the polygraph to specific investigations of job-related wrongdoing - Nonetheless, some governmental agencies in the United States and Canada still use the polygraph as a general screening tool (ex. Police departments and the Canadian Security Intelligence Service (CSIS) also requires that its potential employees take a polygraph test to assess “the candidate’s reliability and loyalty”) TYPES OF POLYGRAPH TESTS - polygraphs are sometimes called a lie detector but the polygraph does not detect lies per se, since the physiological states associated with lying share much in common with many other states, including anxiety, anger, embarrassment, and fear - Instead, polygraph tests rely on measuring physiological responses to different types of questions - Some questions are designed to elicit a larger physiological response in guilty individuals than in those who are innocent 1. THE COMPARISON QUESTION TEST (CQT) - aka Control Question Test - most commonly used test to investigate criminal acts - first the examiner becomes familiar with the case - next the examiner meets the suspect and conducts a pretest trial interview, which the suspect is asked about the offence -m the protest interview is a critical component of this technique

- the examine develops comparison questions, learns abt the background of the suspect and attempts to convince the suspect of the accuracy of the polygraph tests - During this stage the examiner develops a series of ‘yes’ or ‘no’ questions - three types of questions are asked: 1) irrelevant questions, 2) relevant questions and 3) probable-lie comparison questions (control questions) - control questions are defined to be emotionally arousing and focus on honesty and past history - polygraphers assume they can detect deception by comparing reactions to relevant and comparison questions - then, during the testing phase, the examiner then connects the suspect to the polygraph and measures the suspect’s physiological response to the questions - The questions are repeated three to five times in different order - The examiner then scores the physiological responses and ends the CQT with a post-test interview in which the test results are discussed - Guilty suspects are assumed to react more to relevant questions than comparison questions - In contrast, innocent suspects are assumed to react more to comparison questions than relevant questions - The reasoning behind these assumptions is that innocent peo- ple know they are telling the truth about the relevant question, so they will react more strongly to general questions about their honesty and past history. - examiners today now numerically score the charts to ensure that decisions are based solely on the physiological responses - a polygraph test has three possible outcomes: 1) truthful, 2) deceptive and 3) inconclusive - the examiner tells the suspect the outcome during the post-test, and if the outcome is deceptive then the examiner attempts to obtain a confession - psychologist has questioned the underlying rationale of the CQT

2. THE CONCEALED INFORMATION TEST (CIT) - developed by Lykken (1960) and was originally called the Guilty Knowledge Test - the CIT does not asses deception but instead seeks to determine whether the suspect knows details about a crime that only the person who committed the crime would know - the general format of the CIT is a series of m/c questions - each questions has one correct option (aka the critical option) - and four options that are foils (alt that could fit the crime but are incorrect) - The guilty suspect is assumed to display a larger physiological response to the correct option than to the incorrect options - An innocent person, conversely, who does not know the details of the crime, will show the same physiological response to all options - Underlying the CIT is the principle that people will react more strongly to information they recognize as distinctive or important than to unimportant information - suspects who consistently respond to critical items are assumed to have knowledge of the crime - . If ten questions are asked, the odds that an innocent person will consistently react to the critical alternative are exceedingly small (less than 1 in 10 000 000) - Critics of the CIT have warned that this test will work only if the suspect remembers the details of the crime (criminals may not remember specific details or may have memory interference from past crimes) - the most common physiological response measured when administering the CIT is palmar sweating (skin conductance response) - although law enforcement in US and CAD doesn’t routinely use the CIT, it is used regularly in a limited number of jurisdictions, such as Israel and Japan - Iacono and Patrick (1999) suggested two reasons for the lack of widespread acceptance of the CIT - First, since polygraph examiners believe in the accuracy of the CQT, they are not motivated to use the more difficult-to-construct CIT - Second, for law enforcement to use the CIT, salient features of the crime must be known only to the perpetrator. If details of a crime appear in the media, the crime-related details given cannot be used to construct a CIT.

VALIDITY OF POLYGRAPH TECHNIQUES TYPES OF STUDIES - how is the accuracy of polygraph test assessed? - accuracy is determined under ideal circumstances by presenting info known to be true and false to individuals and measuring their corresponding physiological responses - In practice, studies assessing the validity of polygraph techniques vary in how closely they are able to achieve this ideal - studies of the validity of polygraph techniques can be classified into two types: laboratory and field studies 1) Laboratory Studies - Volunteers come to a laboratory and are randomly assigned to one of two conditions: committing a mock crime or not committing a mock crime - The main advantage of these studies is that the experimenter knows ground truth (i.e., who is truly guilty or innocent - In addition, laboratory studies can also compare the relative merits of different types of polygraph tests and control for variables such as the time between the crime and the polygraph exam - However, because of the large motivational and emotional differences between volunteers in laboratory studies and actual suspects in real-life situations, the results of laboratory studies may have limited application to real life - In laboratory studies, guilty participants cannot ethically be given strong incentives to “beat” the poly- graph, and both guilty and innocent participants have little to fear if they “fail” the polygraph exam \ - involve real-life situations and actual criminal suspects, together with actual polygraph examinations - often compare the accuracy of “original” examiners to “blind” evaluators - Original examiners conduct the actual evaluation of the suspect - Blind evaluators are provided with only the original examiner’s charts and are given no information about the suspect or the case - Original examiners are exposed to extra polygraph cues—information about the case in addition to that obtained via the polygraph, such as the case facts and the behaviour of the suspect during the examination - Although polygraph examiners are taught to ignore these cues, Patrick and Iacono (1991) found that examiners are nonetheless significantly influenced by them - the biggest problem with field studies is establishing ground truth, indicators of guilt, (evidence, eyewitnesses, DNA) are often not available, thus the truth is more difficult to establish - two additional ways of establish ground truth have been developed: 1. Judicial outcomes (can be problematic due to false convictions or those guilty aren’t convicted) 2. Confessions (can be problematic due to false confessions) - as well, confessions are not independent from the polygraph examiners decisions, confessions are often elicited bc a person fails a polygraph exam

- what about cases in which a guilty suspects passes the polygraph? (Not included in research studies) - therefore, reliance on confessions to establish ground truth likely inflates polygraph accuracy rates - most field studies have used confessions to estb ground truth POLYGRAPH TESTS: ACCURATE OR NOT? - the accuracy of the polygraph for detection lies is debatable - numerous lab studies have assessed the accuracy of the CQT & CIT - however, there are problems when relying on typical mock-crime scenarios to estimate real-life accuracy - Since the CIT is almost never used in Canada or the United States, no relevant North American data are available. Thus, we will describe assessments of the CIT based on laboratory and field studies done in Israel - Although the CQT has been investigated for more than 30 years, its ability to accurately measure deception remains controversial - Most of the studies have used confessions to classify suspects as guilty or innocent, and as noted above, there are problems with using this as the criterion - Most guilty suspects (84% to 92%) are correctly classified as guilty - However, the picture for innocent suspects is less optimistic, with accuracy rates ranging from 55% to 78% - many innocent suspects were classified as inconclusive - Between 9% and 24% of innocent suspects were falsely identified as guilty - Such a high false-positive rate indicates that innocent people respond more to relevant than comparison questions, suggesting that the premise underlying the CQT does not apply to all suspects. - Mock-crime laboratory studies evaluating the CIT indicate that it is very effective at identifying innocent participants (hit rates of up to 95%) and slightly less effective at identifying guilty participants (hit rates between 76% and 85%) - a meta-analysis of 80 CIT studies examined what factors are associated with higher accuracies - Correct outcomes were better in studies that included motives to succeed, verbal response to alternatives, five or more questions, and in laboratory mock-crime studies - Two published field studies, both done in Israel, have assessed the accuracy of the CIT. Elaad (1990) found that 98% of innocent suspects were correctly classified, but only 42% of guilty suspects were correctly classified - Elaad, Ginton, and Jungman (1992) measured both respiration and skin conduct- ance and found that 94% of innocent and 76% of guilty suspects were correctly classified) - Based on the research described above, the CIT appears to be vulnerable to false- negative errors (falsely classifying guilty suspects as innocent), whereas the CQT is vulnerable to falsepositive errors (falsely classifying innocent suspects as guilty) CAN THE GUILTY LEARN TO BEAT THE POLYGRAPH? - is it possible to use countermeasures to beat the polygraph?

- Honts, Raskin, and Kircher (1994) showed that 30 minutes of instruction on the rationale underlying the CQT was sufficient for community volunteers to learn how to escape detection in a mock-crime study - Participants were told to use either physical counter- measures (e.g., biting their tongue or pressing their toes on the floor) or mental countermeasures (e.g., count- ing backward by 7 from a number greater than 200) when asked a com- parison question during the poly- graph exam - Both countermeasures worked, with 50% of the guilty suspects beating the polygraph test - In addition, the polygraph examiners were not able to accurately detect which participants had used the countermeasures - Iacono, Cerri, Patrick, and Fleming (1992) investigated whether anti-anxiety drugs would allow guilty subjects to appear innocent on the CIT - they conducted a study and determined that none of the drugs had an effect on the accuracy of the CIT, additionally, the polygraph examiner was able to identify 90% of the participants receiving drugs SCIENTIFIC OPINION: WHAT DO THE EXPERTS SAY? - Most knowledgeable scientists are skeptical about the rationale underlying the CQT and its accuracy - But what does the public believe? - Both experts and the public are not very supportive of the polygraph and using the results in courts - However, the public does have more positive beliefs concerning the accuracy of the polygraph - For example, experts are much less likely to agree that the CQT is 85% accurate at detecting a guilty person (27%) as compared to the general public (75%) - “The theoretical rationale for the polygraph is quite weak, especially in terms of differential fear, arousal, or other emotional states that are triggered in response to relevant and comparison questions” (NRC, 2003, p. 213) - Despite scientists’ negative view of it, the CQT is still used by law enforcement as an investigative tool - To understand why, we have to know only that whatever its actual validity, the polygraph will cause many suspects to confess, thereby providing resolution of the criminal investigation

ADMISSIBILITY OF POLYGRAPH EVIDENCE - Polygraph results were first submitted as evidence in court in the United States in Frye v. United States (1923) - James Frye was denied the opportunity to have the results of a polygraph test conducted by William Marston admitted as evidence - This ruling led to the requirement that a technique must obtain “general acceptance” by the relevant scientific community before it can be admitted as evidence - Polygraph evidence is not admissible in Canadian criminal courts of law - In R. v. Beland (1987), the Supreme Court of Canada ruled that polygraph evidence should not be admitted to help to determine whether a person is telling the truth - The court referred to the polygraph as being falsely imbued with the “mystique of science,” thus causing jurors to give polygraph evidence more weight than it deserves when determining the verdict BRAIN-BASED DECEPTION RESEARCH - In the past decade, researchers have attempted to use brain-based responses to detect deception - Event-related brain potentials (ERPs) are a type of brain-based response that has been investigated for detecting deception - ERPs are measured by placing electrodes on the scalp and by noting changes in electrical patterns related to presentation of a stimulus - ERPs reflect underlying electrical activity in the cerebral cortex - One type of ERP that has shown promise is known as the P300 - This ERP occurs in response to significant stimuli that occur infrequently - When using CIT procedures, guilty suspects should respond to crime-relevant events with a large P300 response, compared with their response to noncrime-relevant events - No difference in P300 responses to crime-relevant and irrelevant events should be observed in innocent suspects - One of the advantages of ERPs is that they have been proposed as a measure resistant to manipulation - Several studies have been conducted to assess the validity of the P300 as a guilt detector - Farwell and Donchin (1991) conducted one of the first studies on the use of the P300 to detect the presence of guilty knowledge. - the results looked impressive, but there were several limitations to this study - Abootalebi and colleagues (2006) recently reported lower detec- tion rates than previously reported (e.g., Rosenfeld et al., 1991) when employing the P300-CIT paradigm, with correct identification ranging from 74% to 80%, depending on the approach. - More recently, Farwell (2012) described the P300-MERMER response, which is a longer ERP wave form - Farwell claims that this brainwave response is a more accurate meas- ure of concealed knowledge in tasks that are more complex, such as actual criminal cases. - A possible new lie-detection technique using functional magnetic resonance imaging (fMRI) has been examined

- fMRI measures the cerebral blood flow (a marker of neurological activity) in different areas of the brain - The appeal of using a brain-based lie detection approach is that instead of measuring emotional arousal, researchers hope that it measures the actual process of deception - Researchers have used fMRI to determine which areas of the brain are associated with deception in a variety of deception paradigms, including forced-choice lies, spontaneous lies, rehearsed lies, faking memory impairment and concealed information tests - The most consistent finding from the studies is that the lie conditions produce greater activation in the prefrontal and anterior cingulate regions as compared to truth conditions - These findings and others indicate that brain-imaging techniques can dif- ferentiate which parts of the brain are involved in lying and may even indicate which areas are associated with different types of lying - fMRI laboratory studies have found that deceptive and honest responses can be detected at accuracies around 90% - investigated whether a simple covert movement (e.g., move your left toe) would impact the accuracy of the fMRI in a concealed information paradigm. When participants did not use this countermeasure, deception detection accuracy was 100%, but it was only 3...