Directed Lie Comparison Questions and Countermeasure Resistance

Research suggesting modern directed-lie formats may offer better countermeasure resistance than probable-lie CQT.

Experimental examination of countermeasure effectiveness against directed-lie versus probable-lie formats.

Published in 2015 in Various publications, this work by Honts and colleagues examined directed lie comparison questions and countermeasure resistance. Key findings include: Examined whether directed-lie comparison questions offer better countermeasure resistance. Research suggests that modern testing formats with directed lies may be more robust against deliberate manipulation attempts. Understanding countermeasure vulnerability is essential for maintaining the integrity of polygraph testing programs.

If confirmed, this countermeasure resistance advantage adds to the multiple benefits of directed-lie formats.

Background & Context

The comparison question polygraph test (CQT) has long relied on two distinct approaches to comparison questions: the traditional probable-lie format and the more modern directed-lie format. While directed lie comparison questions have been in use by some government agencies since the late 1960s and described in research since at least 1981, debate has persisted about which format offers superior performance, particularly regarding vulnerability to countermeasures.

Countermeasures—deliberate attempts by examinees to distort test outcomes—represent a persistent concern in polygraph practice. Previous research demonstrated that trained subjects using either physical countermeasures (biting the tongue or pressing toes to the floor) or mental countermeasures (counting backward by 7) enabled approximately 50% of guilty subjects to defeat polygraph tests. This vulnerability raised critical questions about whether modern directed-lie formats might offer better protection against such manipulation.

Understanding countermeasure resistance is essential for maintaining the integrity and credibility of polygraph programs, particularly in national security and law enforcement contexts where stakes are highest. This research addressed a fundamental operational question: do directed-lie comparison questions provide enhanced countermeasure resistance compared to the traditional probable-lie approach?

Research Design & Methodology

The study employed a mock crime experiment with 250 paid participants (126 females, median age 30 years), with subjects randomly assigned to one of eight conditions in a Guilt (Guilty/Innocent) × Test Type (Probable-Lie/Directed-Lie) × Stimulation (Between Repetition Stimulation/No Stimulation) factorial design. This rigorous experimental framework allowed direct comparison of the two comparison question formats under controlled conditions.

Key methodological elements included:

• Data were scored by an experienced polygraph examiner who was unaware of subject assignment to conditions and with a computer algorithm known as the Objective Scoring System Version 2 (OSS2)
• Both human expert and computerized scoring were employed to ensure objectivity
• The design specifically examined spontaneous countermeasure attempts—those arising naturally from examinees without specific training
• Manipulation of between-chart stimulation tested whether discussion between test repetitions affected outcomes

The study measured multiple physiological channels including respiration, electrodermal activity, cardiovascular responses, and vasomotor activity. This comprehensive approach allowed examination of countermeasure effects across different physiological indicators and scoring methods.

Results & Key Findings

The directed-lie and probable-lie formats demonstrated equivalent validity and countermeasure resistance. There were substantial main effects of guilt in both the OSS2 computer scores F(1, 241) = 143.82, p < .001, ηp2 = 0.371, and in the human scoring, F(1, 242) = 98.92, p < .001, ηp2 = .29, indicating both formats successfully discriminated between guilty and innocent examinees.

Critical countermeasure findings included:

• The directed-lie variant did not evoke more countermeasure attempts, and there were no differences between the test types in the number of spontaneous countermeasure attempts made against them
• The directed-lie had equivalent validity with the traditional probable-lie CQT and is more standardized and may offer application advantages
• Vasomotor responses were found to be highly useful in discriminating deception
• Effect sizes for guilt discrimination were large, with partial eta-squared values of 0.371 for computer scoring and 0.29 for human scoring

Although under the controlled conditions of an experiment the probable-lie and the directed-lie variants of the CQT produced equivocal results in terms of detection accuracy, the directed-lie variant has much to recommend it as it is inherently more standardized in its administration and construction. Importantly, the study found no evidence supporting the hypothesis that directed-lie questions would provoke more countermeasure attempts despite their transparent purpose.

Discussion & Significance

These findings challenge assumptions about countermeasure vulnerability in directed-lie testing. Critics had theorized that because directed lies are transparent—examinees are explicitly told to lie—guilty subjects might more easily recognize their function and attempt manipulation. The data refute this concern, demonstrating that spontaneous countermeasure attempts occurred at equivalent rates regardless of comparison question type.

The research aligns with broader meta-analytic findings. Although under controlled experimental conditions the probable-lie and directed-lie variants produced equivocal results in terms of detection accuracy, the directed-lie variant has much to recommend it as it is inherently more standardized in its administration and construction. The literature contrasting the probable-lie and the directed-lie is equivocal, with a large evaluative review of laboratory and field data by the American Polygraph Association looking at variants of the CQT conducted with probable-comparison questions and directed-lie comparison questions and finding no reliable differences.

The standardization advantages of directed-lie testing are particularly significant. Unlike probable-lie questions, which require considerable examiner skill to construct and present effectively, directed-lie questions follow a more uniform protocol that reduces variability across examiners and examinations. This standardization may improve reliability and quality control while maintaining equivalent validity and countermeasure resistance.

Limitations & Considerations

The study examined only spontaneous countermeasure attempts—those arising naturally without specific training. Previous research showed that when subjects received instruction, 55% of countermeasure subjects were able to produce sufficient reactions to comparison questions to avoid detection, and the polygraph examiner was unable to detect the use of the mental countermeasures either from observation of the subject during the examination or from the physiological data. The current research did not address whether trained countermeasures would differentially affect the two formats.

Additional limitations include:

• Laboratory setting with mock crime scenario rather than actual field conditions
• Relatively modest incentives compared to real-world consequences
• Median age of 30 years may not represent full demographic diversity of field examinees
• While polygraph tests were shown to be vulnerable to countermeasures in experiments, the frequency and effectiveness of countermeasures in field practice remains anecdotal, an area where additional research is needed

Practical Applications

For polygraph examiners and agencies, these findings support the adoption of directed-lie comparison question formats without concern about increased countermeasure vulnerability. The standardization benefits—easier training, more consistent administration, reduced examiner variability—can be realized without sacrificing accuracy or countermeasure resistance. This is particularly valuable for agencies seeking to implement evidence-based, quality-controlled testing programs.

For examinees and consumers of polygraph services, understanding that both formats demonstrate equivalent performance helps contextualize test results. The transparency of directed-lie questions may actually enhance the perceived fairness and face validity of the examination process. However, vulnerability to countermeasures is common to all tests where the subject has something to gain or lose from the outcome, and the CQT is not at all unique in this regard—the existence of countermeasures should no more eliminate the CQT from applied use than it would any IQ test, personality test or other psychological assessment.