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THE LIE DETECTOR (POLYGRAPH) EXAMINATION PHASES
A polygraph examination consists of three distinct phases:
I. Pre-Test Phase (Information Collection, Relevant Questions/Statements Formulation);
II. In-Test Phase - Polygraph Examination (Chart Collection);
III. Post-Test Phase (Data Analysis, Scoring Procedure).
I. PRE-TEST PHASE (Information Collection, Relevant Questions/Statements Formulation)
During this first phase the examiner will:
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obtain the examinee’s/client's version of the facts regarding the specific issue under investigation;
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formulate and review with the examinee/client all the questions that will be asked during the polygraph examination.
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provide the examinee with a detailed explanation of the polygraph procedure, as well as the polygraph instrument and its components.
I.Pre-Test Phase
II. In-Test Phase
II. IN-TEST PHASE / POLYGRAPH EXAMINATION (Chart Collection)
The polygraph examination takes place during this second phase. Just before beginning the examination, the blood pressure cuff will be inflated to a pressure of 60 mmHg. The examiner will then ask the examinee the series of questions that were formulated and reviewed during the pre-test interview. This series of questions will be asked a minimum of three times. As the examinee answers the questions, his or her physiological data are continuously collected, measured, and recorded by the polygraph instrument.
The examinee will have a relaxation period of approximately two minutes between each series of questions..
III. Post-Test Phase
III. POST-TEST PHASE (Data Analysis, Scoring Procedure, Results).
During this last phase, the examiner will analyse and evaluate the physiological data by means of scientifically-based numerical quantification system, and will render one of the following results:
No Deception Indicated: The examinee is telling the truth.
Deception Indicated: The examinee is not telling the truth.
Inconclusive: The evaluation of the examinee’s physiological data is inconclusive.
(less than 5% of all conducted tests).
The Polygraph Instrment
THE POLYGRAPH INSTRUMENT
The computerised polygraph instrument collects, measures, and records physiological data obtained from three major systems in the human body, all of which are controlled by the Autonomic Nervous System.
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Cardiovascular System: Heart rate, relative blood pressure, blood volume;
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Respiratory System: Respiratory activity;
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Electrodermal System: Galvanic skin response, i.e., sweat gland activity.
Following the pre-test interview, the polygraph examiner will place various painless components on and around the examinee’s body, thereby connecting him or her to the polygraph instrument. These components are equipped with sensors that serve to collect the examinee’s physiological data as he or she answers the series of previously reviewed questions during the course of the polygraph examination.
The Sensors:
1) A standard blood pressure cuff applied to the examinee’s upper left arm for the purpose of recording cardiovascular activity;
2) Two convoluted rubber tubes (called pneumographs), placed over the examinee’s chest and abdomen to record respiratory activity;
3) Two small metal plates (called galvanometers), attached to the fingers of the examinee’s right hand to record Galvanic skin response, i.e., sweat gland activity;
Calibration Test
STIMULATION/CALIBRATION TEST
Before beginning the polygraph examination, the examiner will administer a stimulation/calibration test. The purpose of this test is threefold:
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To find and fix examinee's physiological baseline at the time of the test through which the expected nervousness or anxiety of the examinee will not affect the test.
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To obtain adequate tracings of the examinee’s physiology to ensure that he or she is a suitable candidate to undergo a polygraph examination.
Polygrah Examination Report
POLYGRAPH EXAMINATION REPORT
Upon completion of the polygraph examination, the examiner will provide the client with a verbal result. A written verified report, detailing the information received during the polygraph procedure and the examination result, will be sent to the client (at no extra cost) within 24 hours after the test completion.
Systems and Methodology
Booking and Confrmation Phase
SYSTEMS AND METHODOLOGY
All polygraph examinations are administered in accordance with the Code of Ethics and the set of Standards and Principles of Practice required by the American Polygraph Association (APA) - the world's leading association dedicated to the use of evidence-based scientific methods for credibility assessment.
Our firm utilizes state-of-the-art digital polygraph systems from Lafayette Instruments (Global leader in polygraph instrumentation) optimized with the last LxSoftwear version 11.8.5.
BOOKING AND CONFIRMATION PHASE
The booking process is automated, secure and designed to take only a few minutes to complete. Once the services of our firm have been retained by clicking on the button ''Book Now'' and paying the required deposit of £150 (Fees and Cancellation policy apply), the requester of the lie detector test (polygraph examination), also referred to as "the client" will receive an email with a link to our pre-examination assessment form which should be filled and submitted online no later than 48 hours after the deposit has been made.
Shortly after paying the remaining balance for the requested test(s) by using one of our secure payment methods integrated in our form, the client will receive a final confirmation email with the date/time/address of our controlled office location (outside London) where the test will be conducted (except if the client chose his own residential/private address for the test).
IMPORTANT: The client must provide accurate information when filing the pre-examination assessment form as this will serve as the foundation for the polygraph examination.
The formulation of the Relevant Questions/Statements for the polygraph test will be done on the day of the examination during the pre-test interview with our accredited examiner.
The client must establish all case facts to the examiner by way of a full and rigorous investigation.
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