**Please note, at the bottom of this article there is a downloadable PDF test report of a Sample Directed Lie test. After reading this article, please download the report for additional in-context information**
Explanation of Directed Lie Test Report
The following information explains test report results for EyeDetect which use the Directed Lie test protocol. Included is basic background information, as well as other details directly related to the question of nature and scope of directed lie questions.
Cognitive Load
Theories of deception detection hypothesize that lying is more cognitively demanding than telling the truth. [1] Deceptive individuals use cognitive resources to inhibit the truth, fabricate the lie, and maintain its consistency, coherence, and believability over time.
Deceptive individuals may also surveil their own behavior and internal state of arousal to self-monitor whether they are leaking incriminating information, especially during an interrogation or examination [2]. During interrogation, they may also use additional cognitive resources to observe the behavior of any interviewers for feedback on their own perceived believability.
Inhibiting truthful responses, attempting to maintain credibility over time, monitoring the interviewer and self-monitoring for signs of information leakage are cognitive processes that require mental effort, and then distinguish deceptive from truthful individuals.
Lying requires more mental effort than being truthful, and physiological correlates of mental load are measurable.
Psychologists have long known there is a strong correlation between cognitive load and certain eye behaviors. For example, pupils dilate commensurate with increases in cognitive workload.[3] Classic studies conducted in the 1960’s revealed that the pupils dilate slightly when a person mentally multiplies 7 x 3 but dilate much more when the person attempts to multiply 17 x 31.
In the same way, the pupils dilate slightly when people respond truthfully to questions; but when they respond deceptively, the pupils dilate more. The pupils dilate more when the person is deceptive because it is mentally more difficult to lie than to tell the truth.
Guilty individuals experience an increase in cognitive load that is revealed by other ocular-motor measures as well. Other important indicators of cognitive processes associated with deception
include reductions in blink rate, response time, fixations, reading time, and rereading time. The effects of deception on these measures are more pronounced when the person responds to complex statements.
Test Questions
All lie detection tests use various types of questions to gather data about the examinee being tested. The question sets can include:
- Relevant questions (those related to the primary issue of interest)
- Comparison questions (those related to a secondary issue)
- Neutral or irrelevant questions (those unrelated to the issue).
EyeDetect and polygraph test protocols are similar in that regard. Relevant questions (e.g., Did you rob the bank?) evoke a measurable cognitive response in a guilty examinee. For an innocent examinee, that same relevant question should evoke a smaller cognitive response.
In the same way, polygraph examinations record changes in physiological reactions to relevant questions. Those changes in measured physiology load on one group of questions or the other, as a function of deception or truth telling, are shown with respect to the relevant target questions (Nelson, 2015).
Conversely, the comparison question generally invokes a larger magnitude cognitive response in innocent examinees as compared to the relevant question. These reactions are used to create a within-subject comparison of reactions to the two types of test question. In essence, the examinee’s reactions to the two types of questions are compared to determine if a deceptive or truthful pattern of responses was observed.
In some test protocols, the comparison question is a crime of serious consequence, but one that the examinee is not likely to have committed. In other test protocols, the comparison question is an issue that all examinees are guilty of having committed. Each test protocol has been designed, researched and tested to evoke specific responses in guilty and innocent examinees.
The irrelevant or neutral questions evoke a minimal cognitive response in all examinees but given that neutral questions are unrelated to the issue of primary or secondary concern, that minimal reaction is expected.
Directed Lie Test Protocol
The EyeDetect Directed Lie Comparison (DLC) test protocol is used primarily when conducting diagnostic or specific-issue tests, but it also may be used as a screening test. This questioning technique is similar to the Directed Lie Screening Test (DLST) polygraph protocol which has been in use for three decades (Menges, 2004).
In directed lie tests, EyeDetect and polygraph have similar protocols. They both use relevant questions, comparison questions, and irrelevant questions.
The relevant question asks about the issue of primary concern (i.e., Did you rob the bank?)
The comparison questions are “directed lie” questions. To be specific, the examinee is asked or “directed” to lie when they answer these questions. These are questions that everyone can answer in a similar way. The directed lie questions all begin with a similar phrase, such as “In my entire life,” which is intended to prompt the examinee to remember to lie when responding to that question.
The following are examples:
- In my entire life, I have never told a lie.
- In my entire life, I have never made a mistake.
- In my entire life, I have always been honest.
- In my entire life, I have never broken any laws.
In the pre-test instructions, examinees are told that they must lie to the directed lie questions and react appropriately to them, or they will fail the test. This type of instruction intends to focus the examinee on carefully reading and following instructions. Examinees are led to believe that if they do not follow their instructions, they will fail the test. They are also led to believe that if their bodies do not respond appropriately to the directed lie questions, they cannot pass the test.
Both the relevant and directed lie questions challenge the examinee’s goal of passing the test. The questions that most challenge that goal are those that will cause greater physiologic changes in the examinee. Psychologically speaking, when an innocent person is asked about the relevant issue (bank robbery) and the directed lie questions (having never told a lie or made a mistake), she/he should focus more attention on the directed lie questions to ensure she/he will not fail the test. Innocent people will be less concerned about the relevant questions, since they were not involved and have no memory of involvement in the crime. The innocent person should invest more cognitive effort processing directed lie questions, as they pose the greatest threat to their goal of passing the test. An innocent person should be less concerned about the relevant issue than the directed lie issue and should exhibit a lesser cognitive response for those questions.
On the contrary, a guilty person should invest more cognitive effort while processing the relevant question because it poses the greatest threat to her/his goal of passing the test. That person may experience an emotional response to the threat of detection for the crime of which they are accused. Cognitively, she/he will exert more effort to deny involvement in that crime. The guilty person will be less concerned about the directed lie questions because those questions do not present as great a challenge as do the relevant questions.
Test Report
The EyeDetect test report includes a section “Test Response Summary” that indicates the examinee’s responses to the relevant questions and to the directed lie (comparison) questions.
The following is an example of the test report section for the relevant question (illegal drug use). The left column labeled “Statement” shows the questions asked of the examinee. The second column labeled “Correct Answer” indicates what the expected response would be from examinees taking the test. In other words, whether the examinee is innocent or guilty, unless a guilty person confesses, all examinees deny the use of illegal drugs. Therefore, the “Correct Answer” indicates a denial of that issue. The green circle (correct) or red circle (incorrect) indicate how the examinee responded to each question. If no response, it is called a “Time Out.”
In the example shown above, the examinee responded incorrectly to one of the relevant questions.
Important note: The number of incorrect or correct responses is less important than the intention of the examinee when responding. In other words, if a few answers are incorrect when responding, it will not affect the outcome of the test because when an examinee responds deceptively, the cognitive load invoked will be that which is observed in guilty examinees.
Along the same line, a guilty examinee may answer all test questions correctly while still obtaining a deceptive test score. This occurs because the savvy examinee knows what the correct question responses should be, but the cognitive load invoked will be that of a deceptive individual.
The following image shows a sample test report section for the comparison question (directed lie). The left column labeled “Statement” shows the questions asked of the examinee. The second column labeled “Correct Answer” indicates the requested response for all examinees taking the directed lie test.
In other words, whether the examinee is innocent or guilty, all examinees are asked to lie to the directed lie questions. Therefore, the “Correct Answer” indicates the correct response when lying to that issue. The green circle (correct) or red circle (incorrect) indicate how the examinee responded to each question. If no response, it is called a “Time Out.”
In the example shown above, the examinee did not correctly respond to four of the directed lie questions. This means the person did not lie to those four questions, as instructed. In some instances, this could be due to a lack of concentration or simply because of a mistake.
Regardless, if the examinee intended to answer the questions as instructed, but incorrectly responded, the cognitive load invoked will be similar to that of a person that intended to answer correctly.
[1] Johnson, Barnhardt, & Zhu, 2005; Kircher, 1981; Vrij, Fisher, Mann, & Leal, 2000.
[2] Kircher, 1981
[3] Kahneman & Beatty, 1966
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