What is a polygraph?
The polygraph, often referred to as the "lie detector," is an instrument that records physiological responses caused by the autonomic nervous system. A polygraph examination is a combination of a psychophysiological testing technique and an interview. The instrument itself is a combination of several recording devices routinely used in the medical and scientific community, and it records the physiological changes that occur when the subject is asked questions during the test. The polygraph records respiration, cardiovascular activity, and electrodermal activity.
How reliable is the polygraph test?
There is no doubt that the polygraph is very reliable provided the person using it is properly trained and the technique it uses is validated. The American Polygraph Association (APA) has compiled over 200 studies on the subject. Based on twelve separate studies involving 2174 actual cases since 1980, evidence suggests that qualified polygraph examiners are 98% accurate in their overall decisions.
What Happens During a Polygraph Test?
A polygraph test takes at least 1.5 hours, but can take up to three hours. The test consists of a series of unbiased and objective phases:
- The first phase is the pre-test interview, which includes: obtaining informed consent to conduct the test; completing a medical questionnaire; an explanation of the equipment; Obtaining background data from the examinee and his version of the events. During this time, the examiner will discuss the questions to be asked and familiarize the examinee with the examination procedure. All exam questions are thoroughly reviewed, giving the examinee an opportunity to qualify or clarify their answers
- The next phase is data collection and consists initially of fitting the components, which routinely involves fitting breathing tubes around the subject's upper and lower chest. These tubes record respiratory rate, tidal volume, and breathing patterns. A standard blood pressure cuff is placed on the subject's upper arm and inflated to a slight pressure immediately before the start of the test to record a constant reading of the subject's heart rate and pulse rate; the pressure is then released at the end of the test. Electrodermal activity finger cuffs are placed on two fingers to measure skin conductance (sweat gland activity) and a photoplethysmograph is placed on another finger to measure blood rate volume. The examinee sits on a sensor movement mat. The examiner then analyzes the tables and gives a verdict on the veracity of the person administering the test. Where appropriate, the examiner will provide the examinee with an opportunity to explain physiological responses in relation to one or more questions asked during the test. It is important to note that a polygraph does not involve an analysis of the physiology associated with the voice. Instruments claiming to record vocal stress are not polygraphs and have no scientific backing
- Chart analysis and post-test interview
How fast will I get the results?
The result is available at the end of the exam.
Can't pass the polygraph test if you're nervous?
Being nervous and anxious about a lie detector exam is common and not uncommon. It's also normal to worry about failing the test, even when you know you're telling the truth. Nervousness doesn't make a person fail a lie detector test - lying does.
Can you pass the test?
Provided the examiner administering the test is trained and qualified, this is highly unlikely. The polygraph is a medical instrument that records changes in a person's autonomic reactivity as they answer questions, and if a person engages in behaviors to distort the polygraph recordings, this will become apparent to a trained examiner upon viewing the recordings .
In most cases, it is easy for a qualified examiner to determine if an examinee is attempting to change the result of an examination. If such behavior is detected, a result of “deliberate non-cooperation” will be given.
Are polygraph results admissible in Irish courts?
Polygraph tests are not intended as a means of making a legal verdict, that is the role of the courts and juries. However, there is no reason why the results of a polygraph test cannot be presented as evidence, the judge will decide on a case-by-case basis whether to admit this evidence. In many respects, the polygraph is no different from other devices such as X-ray machines, electrocardiographs, etc., the results of which are admitted as evidence, but expert interpretation is required. Whether or not the results are used in court, the polygraph test has saved investigators and corporations tremendous amounts of investigative costs and resources by narrowing the focus of the investigation and providing additional investigative clues.
What should I look for in a polygraph examiner?
Make sure the examiner was professionally trained at a polygraph school accredited by the American Polygraph Association and has been continuing their education regularly since then. They should use the latest computerized equipment and the latest validated techniques. Make sure your examiner meets each of these requirements.
In addition, it is beneficial to look for a polygraph examiner who has professional affiliations and memberships with recognized associations that set professional standards for their members, such as: B. the American Polygraph Association or the British Polygraph Association. There is currently no Irish Polygraph Association.
How do I know if the examiner is properly qualified?
It is extremely important that you only use an examiner who has been properly trained and is a member of a recognized professional organization such as the American Polygraph Association. All of our examiners are members of numerous professional and recognized organizations including the American Polygraph Association and the British Polygraph Association. This can be independently verified on the websites of these associations. Therefore, when you turn to Lie Detector Ltd you can be assured that your test will be carried out professionally and that your examiner has been trained to the highest standards.
Can someone under 18 take a lie detector test?
Yes, but the examiner must have prior written consent from a parent or legal guardian. Most examiners will not test anyone under the age of 14, however this does not mean that all 14 year olds are good candidates to take a test and this needs to be checked on a case by case basis.
What questions can be asked?
The examiner will work with you to create questions that cover the test topic and follow strict rules for the latest polygraph techniques
Where do you conduct tests?
We conduct tests in Dublin and a number of other locations in the Republic of Ireland and Northern Ireland. Please contact us to discuss your nearest testing location.
How much does an exam cost?
The price may vary depending on the reason for the test. However, our prices are the most competitive and are not overstated by additional fees for an agent or middleman. Call us (01 685 4715) or email us:info@liedetector.ie, tell us the reason for the test and we will confirm the price
Can I be forced to take an exam?
No one can be forced to take an exam, and the examiner will even require you to give your written consent to the exam. We always encourage you to think carefully about how the result of the test might affect you
How do I book a test?
To book a test, just give us a call01 685 4715
FAQs
How can I pass a polygraph every time? ›
So here's how you beat the test: Change your heart rate , respiratory rate, blood pressure and sweat level while answering control questions. Send your control lies off the charts. By comparison, your answers to the relevant questions (whether they are truths or falsehoods) will seem true.
Can I cheat a polygraph test? ›A simple way to cheat the polygraph is to deliberately distort your physiological readings when telling the truth, such as by biting your tongue, or imagining an embarrassing incident in the past.
Will they tell you if you fail a polygraph? ›You will not be notified of your results on the spot, but they will be reviewed by another examiner and you will be contacted later with the results.
What are the 3 things measured on a polygraph? ›The instrument typically used to conduct polygraph tests consists of a physiological recorder that assesses three indicators of autonomic arousal: heart rate/blood pressure, respiration, and skin conductivity. Most examiners today use computerized recording systems.
Can you fail a polygraph by being nervous? ›Nervousness may result in a person failing a polygraph test. Even if you aren't lying but because you are nervous, your blood pressure is high, and you are breathing heavily. As lie detectors cannot differentiate between Anxiety, nervousness and lying.
Can someone with anxiety pass a polygraph? ›If you have a mental condition Anxiety, Depression, Bi-Polar, ADHD, ADD or PTSD you as long as your condition is under control, you can sit still, follow directions, breath normally you could successfully undergo an accurate polygraph lie detection examination.
What fails you on a polygraph? ›Lie Detectors have Error Rates. There are two reasons why people fail lie detection tests: The person is guilty and is lying about the issue under investigation. The person is innocent but reacted similarly to persons known to be guilty, based on scientific research studies.
How can an innocent person fail a polygraph test? ›The problem with polygraph tests
It's used to measure levels of fear and physical responses, not actual lies. These tests can fail because a person who is telling the truth could be anxious and a person who is lying might not be anxious at all.
A small dose of the widely used tranquilizer meprobamate allows people to lie without detection in polygraph, or lie-detector tests, according to a report in the journal Science.
How far back does a polygraph go? ›Polygraph examinations must have been conducted within the past two (2) years or within the last seven (7) years if hired and still (continuously) employed in that position for which the applicant was hired. Examinations conducted outside of a 7-year timeframe will be reviewed for partial reciprocity.
How long does it take to hear back after a polygraph? ›
6 to 8 months. The background is what takes the longest. Sometimes the people you put down work or phone or something has changed. The your criminal record must be checked throughly.
How long does it take to get the results of a polygraph test? ›Barring extenuating circumstances, you will receive final results and a written report within 24 hours of the exam. How can I pay for my polygraph exam?
What is a good score on a polygraph? ›Analogous to the Likert scale is the polygraphic 7-position scoring: –3 (strongly deceptive), -2 (deceptive), -1 (somewhat deceptive), 0 (neutral), +1 (somewhat truthful), +2 (truthful), and +3 (strongly truthful).
What is the most important thing to consider in a polygraph result? ›Calculation of the index for diagnostic tests at various levels of accuracy, using various thresholds, and with a variety of base rates shows clearly that base rate is by far the most important of these factors.
What questions do they ask during a polygraph? ›- Personal history.
- Negative information from other agencies (such as previously failing a polygraph)
- Employment background.
- Criminal behavior.
- Financial information.
- Illegal drug use.
- Alcohol use.
- Illegal or deviant sexual behavior.
According to Goodson, some people who are telling the truth can fail polygraph tests by trying too hard to control their body's responses.
How do you relax a polygraph test? ›Get A Good Night's Sleep
So long as you are forthcoming with all questions asked by the polygraph examiner and tell the truth, you will do well. With that said, it is important to get a good night's sleep. Try to stop worrying. Eat a satisfying meal, relax and go to bed with enough time to get 6-8 hours of sleep.
Be honest. Answering questions honestly is the most important part of taking a pre-employment polygraph test. Remember that your polygraph results are private, so only you and your employer can access them. You should also understand that being honest about a past mistake won't always disqualify you from a job.
Does sleep affect a polygraph? ›Sleep deprivation in a subject reduces the accuracy of a POT test polygraph examination. Such a lack of sleep reduces the accuracy to a level that renders the test useless. Energy drink intake by people with sleep deprivation increases the accuracy of a POT test polygraph examination.
What are the odds of beating a polygraph? ›The American Polygraph Association, which sets standards for testing, says that polygraphs are "highly accurate," citing an accuracy rate above 90 percent when done properly. Critics, however, say the tests are correct only 70 percent of the time.
What percentage of people fail polygraphs? ›
Mark Handler, editor in chief of the American Polygraph Assn., said failure rates of about 30% are typical in law enforcement hiring.
How often do innocent people fail a polygraph? ›If a person claims to be telling the truth and fails a polygraph, then such a person should be given the opportunity to take another, because the probability of an innocent person failing two tests is 4.0% (.
Does pain affect a polygraph test? ›People with physical challenges—such as an individual who is in a wheelchair—require special care which needs to be considered when requesting a truth verification exam. In many cases, it would be impossible or inhumane to give someone a polygraph if they are in pain or physically incapacitated.
What is the final and most crucial part of any polygraph examination? ›Chart analysis is the final and most crucial part of any polygraph examination. This phase of study teaches the student how to understand the physiological phenomena recorded by the instrument, to make the proper and necessary comparisons, and to reach an accurate conclusion of truth or deception.
Can you drink the day before a polygraph? ›Don't drink alcohol or smoke marijuana for at least 12 hours before your test and if you did tell the examiner about it so they can determine if the test should proceed or reschedule. Take all your prescribed medications on time and as directed by your doctor. Get a good night sleep the night before the test.
Is a polygraph 100%? ›They estimate the accuracy of the polygraph to be 87%. That is, in 87 out of 100 cases, the polygraph can accurately determine if someone is lying or telling the truth. That sounds pretty impressive, but it is important to keep in mind that the polygraph is failing 13% of the time.
What are the four possible result of a polygraph examination? ›The polygraph measures physiological responses that correspond to this arousal: galvanic skin response, respiration, heart rate, and relative blood pressure.
How often is a polygraph wrong? ›There have been several reviews of polygraph accuracy. They suggest that polygraphs are accurate between 80% and 90% of the time. This means polygraphs are far from foolproof, but better than the average person's ability to spot lies, which research suggests they can do around 55% of the time.
How do I know if I passed polygraph? ›The organization that is administering the polygraph exam or AKA the lie detector test will most likely inform you that you have passed or failed. You will also be able to know if you are seeking employment that often the process will be immediately terminated or end shortly afterward if you have not passed the exam.
Do polygraph examiners bluff? ›In reality, this is another way of badgering the subject into a damaging admission. Some polygraph operators routinely bluff every subject this way, whether or not the charts indicate deception at all.
Can a truthful and innocent person fail a polygraph test? ›
The results of a lie detector test are unreliable, and many innocent people have failed them. Even if you pass the test, this does not mean that you will not be charged with committing a crime.
How many questions can you ask on a lie detector test? ›How many questions can I ask? All scientifically validated lie detector techniques limit a single lie detector test to the use of no more than four (4) pertinent questions per test.
Which 3 physiological changes are measured with a polygraph? ›This appendix summarizes scientific knowledge about the three main physiological processes that are measured by the polygraph: cardiovascular, electrodermal, and respiratory.
How do guilty people pass polygraphs? ›The generally acknowledged tactics for beating a polygraph machine are to carefully control your breathing, and to artificially increase your heart rate during what are called "probable lie" or "control questions." These include questions people are likely to lie about such as, "Have you ever stolen money?" "Have you ...
Can you outsmart a polygraph? ›Defeating a polygraph against novice students is possible, but defeating an experienced examiner is harder. Goodson says that although he can successfully defeat a polygraph against novice students, defeating an experienced examiner is harder.
Why do I keep failing polygraph? ›Lie Detectors have Error Rates. There are two reasons why people fail lie detection tests: The person is guilty and is lying about the issue under investigation. The person is innocent but reacted similarly to persons known to be guilty, based on scientific research studies.
How can you fail a polygraph if you tell the truth? ›The problem with polygraph tests
It's used to measure levels of fear and physical responses, not actual lies. These tests can fail because a person who is telling the truth could be anxious and a person who is lying might not be anxious at all.
Get A Good Night's Sleep
So long as you are forthcoming with all questions asked by the polygraph examiner and tell the truth, you will do well. With that said, it is important to get a good night's sleep. Try to stop worrying. Eat a satisfying meal, relax and go to bed with enough time to get 6-8 hours of sleep.
It is important to note that FBI polygraph failure rates are remarkably consistent with other federal agencies. For instance, the Secret Service reportedly has a polygraph failure rate of 35 percent, while the U.S. Drug Enforcement Agency has a 36 percent failure rate.
Can you fail a polygraph and be innocent? ›The results of a lie detector test are unreliable, and many innocent people have failed them. Even if you pass the test, this does not mean that you will not be charged with committing a crime.
What if you are nervous during a polygraph? ›
Is there a possibility of failing the lie detector test when you are nervous? The lie detector test takes note of the physical responses which may include the heart rate or the breathing. Thus, provided that your feelings and emotions do not induce a direct physical response, there should be no problem with the test.
How many innocent people fail polygraphs? ›If a person claims to be telling the truth and fails a polygraph, then such a person should be given the opportunity to take another, because the probability of an innocent person failing two tests is 4.0% (.
How accurate is a polygraph test 2022? ›However, strong polygraph responses may also be due to shock or upset at the question or nervousness about the polygraph itself. So how accurate are polygraphs in actually detecting lies? There have been several reviews of polygraph accuracy. They suggest that polygraphs are accurate between 80% and 90% of the time.
How does a polygraph test know you're lying? ›A polygraph test measures and records the physiological responses of a subject while he or she answers a series of questions. Careful analysis of the physiological responses can indicate when the person is lying.