Derived from the Greek language, the word "polygraph" means "many writings". It refers to the manner in which selected physiological activities are continuously and simultaneously recorded. The polygraph instrument is often referred to as a "lie detector".
A polygraph is a diagnostic instrument used by a formally trained polygraph examiner for the purpose of collecting, measuring, and recording selected physiological data obtained from an examinee as he or she answers a series of questions relating to a specific issue — whether criminal, civil, or private — during a polygraph examination. This data will then be analyzed and evaluated for psychophysiological credibility assessment.
Polygraph examinations are used in more than 50 countries by government organizations worldwide, law enforcement agencies, private security firms, the legal community, the corporate sector, and private citizens.
The development of medical-grade instrumentation and software has allowed for computerized polygraphs to record physiological responses directly to a software program and display this data on a computer monitor.
During a polygraph examination, the polygraph instrument detects, measures, and records physiological data obtained from three major systems in the human body, all of which are controlled by the Autonomic Nervous System:
1) Respiratory System: Respiratory activity patterns and changes;
2) Cardiovascular System: Heart rate, relative blood pressure, blood volume;
3) Electrodermal System: Galvanic skin response, i.e. sweat gland activity.
The polygraph technique is extremely accurate as there have been studies by doctors and scientists for over 50 years. Most importantly the polygraph is accurate when done by a qualified, credible and experienced examiner. The Lie Detector Test or Polygraph examinations have gained general acceptance in the scientific fields of psychology and psychophysiology in those areas devoted to credibility assessment. Research conducted by the relevant scientific community, government organizations, and independent universities clearly indicate that a polygraph examination — when properly administered by a formally trained and competent polygraph examiner — has a very high level of accuracy (on average 90 to 95%) in verifying the truth and detecting deception.
According to Dr David C. Raskin, the world-renowned expert and leading scientist in the field of polygraphy, the scientific data concerning the validity of the polygraph can be summarized as follows:
"High quality scientific research from the laboratory and the field converge on the conclusion that a properly conducted CQT (Comparison Question Test) is a highly accurate discriminator of truth tellers and deceivers. The research results converge on an accuracy estimate that exceeds 90 percent."
According to the American Polygraph Association (APA), 80 research projects, which included both laboratory and field studies, have been conducted and published since 1980 on the validity and reliability of polygraph testing. These projects involved approximately 6,300 polygraph examinations. Of the 23 field studies conducted, the accuracy of polygraph testing was estimated to be 95 percent.
Like any other diagnostic instrument that is used to measure human physiology for the purpose of evaluation and forming professional opinions thereupon, the polygraph instrument is not infallible. The relevant scientific community agrees, however, that polygraph examinations have a very high probative value in distinguishing truthful individuals from deceptive ones, and that no other alternative testing technique for truth verification and lie detection performs better.
The polygraph instrument is a scientific, diagnostic instrument which is often referred to as the "lie detector". It should be moret accurately be referred to as the "truth verifier".
Under no circumstances will we assist in any case requesting help in a matter of a criminal / illegal / unethical nature. We have had calls where a client will request for a result to be changed / faked to help them pass due to their current situation they are in. We will not entertain such requests. None of our examiners ever have or will take a bribe or favour a client to 'swing' a result. We have to remain ethical, professional and honest and our reputation is at stake. We will not book any tests where we do not have enough case facts before the time and if we are not comfortable with the facts provided we will not conduct the test. No refunds will be given on such bookings. If any danger is posed to the examinee or the case matter we think could be of an illegal nature (theft, sex, drugs) we will report this to the police. Polygraph tests cannot be used to help in the conducting of a crime. Please do not contact us to assist in such matters.
It is quite normal for an innocent person to feel nervous and the polygraph examiner is fully aware of this. The examiner is trained how to calibrate and make the examinee acquainted with the process and instrument. An acquaintance test is done as the 1st chart prior to running anything from 3 - 5 charts around the issue.
A typical example for people to understand is if you are walking down a street at night and you are nervous. Your heart is beating, possibly developing sweat, your breathing is faster. While walking a dog jumps out and barks at you. Immediately you develop one of the 3 F's. Flight / Fight or Freeze. You will react the same in either of those F's. But your heart beats faster, you create more sweat, your breathing reacts suddenly. The examiner records the charts and asks a series of different types of questions and through science and experience as well as with the aid of scoring software will determine if there is lies or truth in the answers.
Yes. You will be informed of the exact wording of each question that will be asked of you during the course of the polygraph examination. There are no "trick" questions.
A polygraph examination takes anything from 1h45 to 2hrs+, however, some may take more or less time, depending on the nature of the issue under investigation. We do not rush the tests and follow strict protocols. We cannot divert from the set international standards.
The examiner will give a detailed explanation of the polygraph procedure, how the polygraph works, and he will answer any questions that the examinee may have. The examiner will also take a detailed statement as to the case at hand, then review the questions, run an acquaintance test and then run at 3 - 5 charts.
No. The process used is the same no matter what technique is used or how many questions there are. There is a pre test (about 30 mins), in test (about 1hr) and post test phase. The in test phase near the end is the running of the charts. There are multiple questions asked in the technique. Whether you have requested just 1 question or 6, the examiner will have discussed with you how best to formulate various versions of the issue. These are repeated over and over in consecutive charts. We cannot create a quick fix test to ask just 1 question to save on time and cannot ask lists of questions as often thought is the case. There is no validated accurate technique for this and our aim is to provide the most professional and correct results.
No. There are no electric shocks and you will only possibly feel slight discomfort in the blood pressure cuff but this is just for a very short time. The examiner will explain this to you in detail before the examination as well as during the procedure.
The polygraph test questions will vary according to the case issue but all questions are specific and pertinent to the issue to be resolved. Questions only require a "yes" or "no" answer and with no explanation or qualification.
Its important to understand that the polygraph is not a miracle magic wand. It cannot be used to ask wrongly phrased questions and multiple bulk questions at once. Hollywood and TV shows often portray the way in which tests are conducted and the style and number of questions asked, in an incorrect way. We use the most accurate techniques available and recommended by the APA. There are techniques asking 2 to 4 relevant questions for single issue matters. For screening and pre employment we can run up to 6 questions. There are a number of other questions asked at the time all helping in the scoring and baseline. But the total number of relevant questions for your matter is limited. The examiner will explain this to you in detail.
Yes. During the pre-test interview on the day of the test, the examiner will formulate and review with you (the examinee) all the questions that will be asked during the polygraph examination. There will be no surprise or trick questions.
No. No one can be forced to undergo a polygraph test. The test is totally voluntary. To properly administer a polygraph examination, the examiner will need your volunteer assistance by signing a consent form prior to the test. There are few basic instructions which the examinee should follow during the In-test Phase (Chart Collection) as to sit still and not to move needlessly while the examination is in progress. The examiner will also ask you (the examinee) to breathe normally, not to take deep or short breaths, not to hold your breath or to modify it, as all such maneuvers will be detected by the anti-countermeasure sensor and could lead to a termination of the test due to a countermeasure/cheating attempt detection.
Since the examiner requires your full cooperation in this regard, you must voluntarily accept to undergo a polygraph examination.
All polygraph examinations are audio and video recorded for quality and security purposes. This footage is only accessible to the examiner. We do not release any audio or video, as well as polygraph charts to anyone. The report will only be sent in a PDF format on email to the client requesting / paying for the test. The report can also be posted if requested.
Generally no. In order to keep a sterile and confidential environment, no one other than the examiner and examinee can be in the examination room during the procedure. However there are circumstances if an interpreter is needed, or a minor is requesting a parent (who will sit out of site in the corner) or a sign language person is required. Polygraph is a diagnostic procedure which can be adversely affected by unnecessary distractions. No spouse or partner will be allowed in the room or to take any part of the test process (ask the questions) or sit and view in from another area.
Polygraph examinations are used in more than 50 countries such as the USA, South Africa, Spain, Egypt, Israel and Russia. Government organizations, law enforcement agencies, security companies, legal and HR firms, corporates / retails and hospitality as well as private citizens. The UK Government currently has many prison parole officers trained as polygraph examiners. The government does testing on sex offenders on parole. There are more government trained examiners in the UK than private examiners.
https://www.gov.uk/government/publications/domestic-abuse-bill-2020-factsheets/mandatory-polygraph-tests-factsheet
The world wide umbrella body the APA - American Polygraph Association has a model policy updated on 4 Sep 2021 which states that there is NO minimum age to do a test. Previously they had suggested over the age of 12. This is the policy wording:
Examinee suitability . Persons who are suitable to undergo polygraph testing should minimally
meet the following requirements:
4.1. Capacity to consent to the polygraph examination, as demonstrated by awareness and
understanding of the context or reason for the examination referral.
4.2. Possess a basic understanding of right from wrong, and the difference between truth and
lies, as demonstrated by an ability to verbalize potential reasons for being honest or
dishonest, and the potential rewards or consequences for dishonesty or truthfulness; and
4.3. Maintain consistent orientation to date, time, and location, for example: being able to
provide basic identifying information, (i.e., name, address, date, date of birth, etc.) to
complete an authorization form.
Contrary to some claims and what is read on the internet, drugs or medications will not allow anyone to cheat or beat the test. They also will not affect the test to make you fail or even to pass. An example is that if 3 people walk down a street. One has high blood pressure, one has the flu and one has worked a night shift and is tired. A person jumps out with a knife to try and rob them. The reaction is the same for all 3. All of them will have an increase in heart rate, blood pressure will get higher, sweat will develope and breathing changes. The one does not react differently to the other because of the condition they have. There is an automonic reaction that takes place and this is displayed on the charts which is scored by the examiner.
Examiners should not conduct polygraph examinations on individuals determined to be unsuitable. When available, examiners should consider psychological diagnostic information. Individuals deemed unsuitable for polygraph testing should not be tested until the identified conditions have improved, and when the individual is able to adequately attend to the examination context. Conditions that should preclude an examinee from suitability for polygraph testing include the following:
- Psychosis (e.g., lack of contact with reality, including hallucinations or delusional thinking) or psychotic condition that is active, un-treated, or un-managed at the time of the examination;
- Mean Age Equivalence (MAE) or Standard Age Score (SAS) is below 12 years, as determined through standardized psychometric testing (e.g., IQ testing, achievement and/or adaptive functioning);
- Severe mental retardation or measured IQ less than 55, as determined through standardized psychometric testing (e.g., IQ testing, and/or adaptive functioning);
- DSM Axis V Global Assessment of Functioning (GAF) score of 50 or less, (e.g., persons who require continuous observation or assistance due to psychiatric or developmental conditions);
- Any DSM Axis I mental health condition to include a severity specifier of "severe" or "with psychotic features" (i.e., indicative of a high potential adverse outcome) for any disorder; acute serious injury or illness, involving acute pain or distress; or
- Observable impairment due to the influence of prescribed or non-prescribed controlled substances including alcohol.
- Special populations. Examiners should conduct all examinations in a manner that is sensitive to any medical, mental health or developmental issues that may affect the examinee's functioning or the quality of the examination data. There is no published research or theoretical rationale suggesting that any medical, mental health, or developmental issues would result in erroneous examination results for individuals who meet the normal functional requirements for polygraph examinees. Ethical professional and empirical practices suggest that the application of normative data and normative interpretation rules to exceptional individuals (i.e., persons whose functional characteristics are outside the normal range of individuals in an intended population or sample) should always be regarded with caution.
- Medical. Persons with some acute or chronic medical/physical conditions may be regarded as marginally suitable for polygraph testing, at which times the test results should be accordingly qualified and viewed with caution. However, there is no published research or theoretical rationale suggesting that any medical conditions would interfere with the polygraph test or that polygraph testing would interfere with known medical conditions.
- Except as precluded by law or regulations, examiners should note in the examination report any diagnosed acute or chronic medical condition. Medical conditions, including stable injuries, depending on their severity, do not necessarily preclude an individual from being suitable for polygraph testing. However, it may at times be advisable to delay polygraph testing until the prospective examinee's health has improved.
- Examiners should defer to medical professionals when determining the suitability of prospective examinees that are pregnant. Examiners should require a statement or waiver from a physician, or other medical professional, attesting to the fact that the pregnancy is normal and uncomplicated with no expected reason that polygraph testing would interfere with the pregnancy. Examiners should delay polygraph testing of any individual determined to be experiencing a medically complicated or high-risk pregnancy.
- Medications. Persons who require the administration of multiple prescription medications to manage the potentially overwhelming effects of a diagnosed medical or mental health condition may be regarded as marginally suitable for polygraph testing. Test results for these individuals should be accordingly qualified and viewed with caution.
- There is no theoretical rationale or published research suggesting that any medications would result in erroneous polygraph examination results. Clinical commonsense suggests that persons who function optimally while taking prescription medications may produce polygraph examination data of optimal interpretable quality while taking medications as directed by a doctor. There is no way to predict the exact effects of medications for any individual. Medication effects may vary with the types and numbers of medication, dosages, length of time on medications, in addition to the individual's physiology. Some increase in inconclusive results may occur from some medications, however, medications do not act differentially among the polygraph test questions, and no known increase in decision errors is expected from medication use.
Yes. There are no studies by the APA that prove testing a pregnant woman has any negative impact on the result. As we are measuring breathing, sweating and heart rate. Usually in the late stages of pregnancy it would be uncomfortable to sit for a long time and also have instruments such as breathing sensors and a blood pressure cuff attached. We always advise that if you are unsure then to consult a doctor before the time. You also need to make your own mind up to do the test and sign a consent form. If at any stage a pregnant woman is not feeling well or wants to stop the process then this is done.
No and do not attempt this either. Do not rely on what other people may tell you they have heard or seen on TV or read somewhere. There are sites on the internet that try take your money to cheat the test. It is generally considered that a guilty person would want to try cheat. In fact you can't cheat the actual test as we measure reactions from the autonomic nervous system you can't control. Examinees try cheat the examiner. Which is not possible based on our experience. If you are honest you have nothing to worry about. If the examiner picks up that you are attempting to cheat or distort the test, the process will be stopped immediately and the report will indicate that there was a deliberate attempt to manipulate the test and result outcomes. Our examiners are highly trained on ALL measures used to try trick or cheat a test. The software and instruments used are designed to pick up even the faintest attempt at any cheating. Whether this be by breathing, movements, mental tricks or muscle contractions. If you know you are being deceptive, the polygraph will detect that deception. We use anti countermeasure instruments in the test used in motion detection.