Peak of Tension Test (POT): A Focused Approach to Detecting Guilty Knowledge

The Peak of Tension (POT) Test is a specialized polygraph examination technique designed to assess whether an individual possesses guilty knowledge related to a specific event, crime, or issue. Developed by Leonarde Keeler, the test is primarily used after an initial polygraph examination when deception has been indicated. By focusing on specific details that only the perpetrator would know, the POT seeks to evoke physiological responses that indicate recognition or anxiety related to those details.

This article explores the essential elements of the Peak of Tension Test, its methodology, and its practical applications in federal polygraph examinations.

Purpose and Scope of the Peak of Tension Test

The primary goal of the Peak of Tension Test is to determine whether the examinee has knowledge of specific facts related to a crime or incident, which would be known only to the perpetrator, investigators, and the examiner. The test is often employed after a polygraph examination suggests deception, helping to further isolate and confirm knowledge of crucial details.

There are two main variations of the POT:

1. Known-Solution Peak of Tension (KS-POT): This format is used when investigators already know the crucial detail or fact about the crime, and the goal is to determine whether the examinee also knows it.
2. Searching Peak of Tension (SPOT): In cases where the key fact is not confirmed, but the investigators have strong suspicions, the SPOT is used to probe for potential guilty knowledge by presenting a range of possible key choices.

Pretest Phase: Question Review and Preparation

Before the test begins, the examiner conducts a pretest interview with the examinee to review the questions that will be used during the POT. The questions are presented in the order in which they will be asked during the test, ensuring that the examinee understands the sequence and format.

Each question in the POT is constructed to include a preparatory phrase, a prefix phrase, and padding questions. The preparatory phrase introduces the topic, while the prefix phrase is repeated with each question. Padding questions are used to mask the key question and minimize the possibility that the examinee will anticipate the focus of the test.

Example Question Sequence for a Known-Solution POT:

• Preparatory Phrase: “Regarding the amount of money stolen from that wallet…”
• Padding Questions: “Was it $100? Was it $200?”
• Key Question: “Was it $500?”
• Additional Padding Questions: “Was it $600? Was it $700?”

The key question is strategically placed among similar but false options (padding questions) to gauge the examinee’s physiological reaction to the actual detail of the crime.

Conducting the Test: Data Collection

During the POT, physiological data such as heart rate, skin conductivity, and respiratory patterns are measured as the examinee responds to each question. The test typically consists of three charts, each containing the same sequence of questions. In some cases, the sequence may be reversed or altered to prevent the examinee from anticipating the key question.

• Known-Solution POT: The test includes six to nine questions, with only one key question per examination. The key question should never be placed in the middle of the sequence, as this can lead to predictable responses.
• Searching Peak of Tension: The SPOT consists of nine questions, with at least two padding questions at both the beginning and end of the sequence.

If a clear conclusion cannot be drawn after three charts, a fourth chart may be collected using a mixed-sequence format.

Test Data Analysis

Unlike other polygraph techniques that rely on numerical scoring, the Peak of Tension Test uses global analysis. This method evaluates the physiological responses across the charts, focusing on consistent responses to the key question.

The examiner looks for significant physiological reactions—such as changes in heart rate or skin conductance—on at least two of the three charts when the key question is asked. If these reactions are present, the examiner concludes that the examinee has guilty knowledge of the detail in question.

• Significant Responses (SR): If the examinee exhibits consistent responses to the key question across at least two charts, the examiner concludes that the individual likely possesses guilty knowledge.
• No Significant Responses (NSR): If the examinee does not show consistent responses to the key question, it is concluded that they likely do not possess guilty knowledge.

Applications of the Peak of Tension Test

The Peak of Tension Test is commonly used in criminal investigations where there are clear facts or details that only the perpetrator could know. It is particularly useful in confirming guilt or clearing individuals who may have been implicated in a crime but lack detailed knowledge of the event.

In addition to criminal investigations, the POT is also used in national security settings, especially in screening processes to detect espionage or sabotage. The test’s ability to focus on specific, verified details makes it an effective tool for uncovering hidden knowledge that may not be revealed through more general polygraph techniques.

Limitations and Considerations

While the Peak of Tension Test is a powerful tool, there are some limitations and considerations that must be kept in mind when administering the test:

1. Examinee’s Psychological State: The effectiveness of the POT depends on the examinee’s state of mind during the test. If the examinee is overly stressed, anxious, or suffering from a medical condition, their physiological responses may not be reliable. Examiners must ensure that the examinee is in a suitable condition for testing.
2. Known vs. Unknown Solutions: The Known-Solution POT requires that investigators already have a firm grasp of key details related to the crime. In cases where these details are unclear or unknown, the Searching Peak of Tension (SPOT) format may be used, but it is generally less precise than the known-solution format. Investigators must carefully assess which version of the test is appropriate for the situation.
3. Possibility of Countermeasures: While the POT is difficult to manipulate, sophisticated examinees may attempt to use countermeasures to mask their physiological responses. Examiners must be trained to recognize and account for any potential countermeasures during the test.
4. Not a Standalone Tool: The POT is most effective when used in conjunction with other polygraph examination techniques, such as the Zone Comparison Test (ZCT) or the Comparison Question Test (CQT). It is not intended to be a standalone diagnostic tool but rather a method for further probing specific areas of concern.

Best Practices for Examiners

For polygraph examiners, mastering the Peak of Tension Test requires thorough training and attention to detail. Here are some best practices for administering the POT:

• Question Construction: The success of the POT hinges on the examiner’s ability to construct clear, well-sequenced questions. The key question should be positioned among padding questions in such a way that the examinee cannot easily predict its placement. Careful phrasing and consistency are essential for ensuring accurate results.
• Multiple Charts: The use of multiple charts (at least three) is critical to obtaining reliable data. By repeating the question sequence and varying the order of the questions, examiners can reduce the likelihood of anomalies and ensure that the physiological responses are consistent.
• Pretest Review: During the pretest phase, the examiner should carefully explain the test process to the examinee and ensure that they understand the questions. This helps alleviate any unnecessary anxiety that could affect their physiological responses during the test.
• Global Analysis: Examiners should use global analysis to evaluate the data collected during the POT. Rather than relying solely on numerical scoring, global analysis takes into account the overall pattern of physiological responses across the charts, providing a more holistic view of the examinee’s reactions.

Conclusion

The Peak of Tension Test is a critical tool in the field of polygraphy, providing a focused approach to detecting guilty knowledge. By carefully constructing question sequences that isolate key facts, the POT helps investigators determine whether an examinee has knowledge of a crime or event that they should not possess. The test’s reliance on global analysis rather than numerical scoring allows for a nuanced interpretation of physiological responses, making it a valuable technique in both criminal investigations and national security screenings.

Its targeted nature and precise methodology continue to make the Peak of Tension Test an indispensable asset in the detection of deception and the protection of national interests