Table of Contents
The You-Phase Zone Comparison Test (You-Phase ZCT), formerly known as the Bi-Zone Comparison Test, is a polygraph examination technique primarily used in federal testing protocols. This format is particularly valued for its simplicity and effectiveness when focusing on a single relevant issue. Originally designed by Cleve Backster, this method was incorporated into federal practices, with slight modifications, by the U.S. Army Military Police School (USAMPS) in 1961. The Department of Defense Polygraph Institute (DoDPI) continues to teach the You-Phase ZCT as part of its polygraph training curriculum.
This article will provide a detailed exploration of the You-Phase ZCT, outlining its structure, key components, and its practical application in polygraph examinations.
Purpose of the You-Phase ZCT
The You-Phase ZCT is designed to evaluate the truthfulness of an individual by measuring physiological responses to a series of carefully structured questions. This test is particularly useful when there is a single primary issue to address, such as a specific crime or act under investigation. By isolating a single relevant issue, the You-Phase ZCT allows for a focused and streamlined approach to detecting deception.
The test revolves around a series of questions that fall into several key categories:
- Sacrifice Relevant (SR) Question: Prepares the examinee for the relevant questions by easing them into the primary issue.
- Relevant (R) Question: Directly addresses the central issue being investigated.
- Probable-Lie Comparison (C) Question: A comparison question designed to create a physiological response for comparison with the relevant question.
- Irrelevant (I) Question: A neutral question used to establish a physiological baseline.
- Symptomatic (SYM) Question: Detects whether the examinee is concerned about issues unrelated to the specific investigation, potentially affecting test results.
Pretest Phase of the You-Phase ZCT
The pretest phase is crucial for preparing the examinee and ensuring accurate results. During this phase, the examiner thoroughly reviews all questions with the examinee. This is done to minimize any confusion or misinterpretation of the questions and to reduce unrelated anxiety that might affect physiological responses during the test. The pretest review is also essential for establishing trust between the examiner and the examinee, allowing for a more accurate assessment during the polygraph test.
The sequence of questions in the pretest review typically follows this structure:
- Sacrifice Relevant (SR) Question
- Relevant (R) Question
- Comparison (C) Question
- Irrelevant (I) Question
- Symptomatic (SYM) Question
Question Types in the You-Phase ZCT
1. Primary Relevant Questions
Primary relevant questions are designed to directly address the matter being investigated. These questions are crafted to assess the examinee’s involvement in the specific issue and are repeated in various forms to ensure accuracy. For example:
- R5: “Did you steal that Mustang?”
- R7: “Did you steal that Mustang from that parking lot?”
The phrasing of these questions may vary slightly, but they focus exclusively on the main issue under investigation.
2. Probable-Lie Comparison Questions (PLCQs)
Probable-Lie Comparison Questions are broad and designed to elicit a physiological reaction from the examinee. These questions focus on general life experiences unrelated to the investigation, but they require the examinee to answer falsely or uncomfortably, typically about minor past transgressions. For example:
- “Before 1997, did you ever steal anything of value?”
By comparing physiological responses to these questions with the relevant questions, the examiner can better determine whether the examinee is being deceptive about the main issue.
3. Sacrifice Relevant Questions
Sacrifice Relevant Questions introduce the examinee to the relevant issue in a way that prepares them for the specific questions that will follow. These questions ease the examinee into answering about the central issue without creating undue stress. For example:
- “Regarding whether you stole that Mustang, do you intend to answer each question truthfully?”
This type of question helps transition the examinee from the pretest phase to the main test.
4. Irrelevant Questions
Irrelevant questions are neutral and unrelated to the investigation. These are often simple, factual questions used to establish a baseline physiological response. For example:
- “Are you now in Alabama?”
- “Are you sometimes called Tom?”
Since irrelevant questions do not carry emotional or psychological weight, they help the examiner identify the examinee’s normal physiological responses.
5. Symptomatic Questions
Symptomatic questions assess whether the examinee is concerned about issues unrelated to the investigation. If an individual is preoccupied with something outside of the test’s focus, it may affect their physiological responses. These questions are not scored but provide insight into potential external stressors. For example:
- “Is there something else you are afraid I will ask you a question about?”
Data Collection and Analysis in the You-Phase ZCT
The data collection phase involves presenting the examinee with a series of questions from the categories mentioned above. Typically, the examiner collects data across multiple charts, with three charts being standard, but a fourth or fifth chart may be used if the results are inconclusive after the third chart.
After the data collection phase, the examiner evaluates the physiological responses, comparing the examinee’s reactions to the relevant questions with their reactions to the comparison questions. The greatest physiological response is used to assess whether the examinee is being truthful or deceptive.
Test Data Analysis and Opinion Rendering
The You-Phase ZCT uses a numerical scoring system to analyze physiological responses. Each response is evaluated independently, and a score is assigned based on the magnitude of the response. The analysis follows these guidelines:
- Deception Indicated (DI): A score of minus three (-3) or less in any overall vertical spot, or a grand total of minus four (-4) or less across all spots, indicates deception.
- No Deception Indicated (NDI): A score of plus one (+1) or greater in every vertical spot, with a grand total of plus four (+4) or more across all spots, indicates that the examinee is likely being truthful.
- No Opinion (NO): If the test results do not meet the criteria for either deception or truthfulness, the examiner renders a “No Opinion” result, except in cases where administrative issues are present.
Conclusion
The You-Phase Zone Comparison Test is a focused and effective polygraph technique used to determine truthfulness when a single relevant issue is under investigation. By structuring the test around key question categories, such as primary relevant, probable-lie comparison, and symptomatic questions, the You-Phase ZCT provides a reliable method for assessing deception. The use of numerical analysis and multiple charts ensures that examiners can make informed, accurate decisions based on the examinee’s physiological responses.
This method remains a vital tool in federal polygraph examinations and continues to be taught and practiced according to guidelines set by the Department of Defense Polygraph Institute.
