Frequently Asked Questions

What is the singular most important fact about Polygraph Examination everybody should remember?
Everybody should remember that if they lie in the Polygraph examination, the Polygraph instrument WILL detect deception.

Can anyone force me to take Polygraph examination?
In order for a Polygraph examination to be administrated properly you must sit still and not move any part of your body. Since the Polygraphist must have this co-operation from you, you must volunteer for the test. If for any reason you don't want to take the examination, you should certainly refuse the test.

What is crucial to remember when searching for a Polygraph Examiner?
Make sure that the Examiner has completed Polygraph Examiner training in one of American Polygraph Association accredited institutions. The Amercian Polygraph Association requires at least eight weeks training. This will ensure that a validated Polygraph examination is conducted.

What is Polygraph?
The term "poly-graph" means "many-writings" and it refers to the manner in which selected physiological activities are simultaneously recorded. A Polygraph instrument measures at least three physiological reactions; respiratory system (breathing pattern), cardio-vascular activity (blood pressure and blood volume) and galvanic skin response (sweat gland activity). When administrated by a competent examiner the Polygraph test is one of the most accurate means available to determine truth and deception.

Is Polygraph examination dangerous for individual's health?
Not at all. Nevertheless pregnant women should not be tested.

Who uses Polygraph examinations?
According to the American Polygraph Association they are over fifty-seven countries using Polygraph testing within three major segments of communities; Law-enforcement and national security agencies (for pre-employment checking of police candidates and/or screening of existing officers and agents), Legal community (to determine the truthfulness of accuser's statements), Private sector (security companies, corporate organisations, insurance companies etc.), Correctional and Social Services (dealing with sex offenders and child abusers), and Private citizens (in matters not involving the legal of criminal justice system).

Who gets the test results?
Polygraph test results can only be given to a examinee or anyone specifically designated in writing by the examinee, person(s), firm, corporation, or governmental agency, who requested the examination.

How accurate is Polygraph test?
Polygraph examination is the only lie detection technique that has proven independent scientific reliability and validity studies and peer acceptance in the world. It is the only lie detection method directly used by many state and federal government agencies in the world for investigative, security and intelligence purposes than any other detection of deception technique available. The Polygraph instrument is the only reliable, validated tool for detection of deception.

The American Polygraph Association has a compendium of 80 research projects involving 6,380 examinations. Researcher conducted 12 studies of the validity of field examinations, following 2,174 field examinations, providing on average accuracy of 98%. In addition researcher conducted 11 studies involving the reliability of independent analysis of 1,609 sets of charts from field examinations confirming by independent evidence, providing an average accuracy of 92%.

Summaries from some of additional studies of Polygraph examination accuracy;

Bersh, P.J. (1969). Journal of Applied Psychology, 53(5), 399-403.
The lie detection judgments of Polygraph examiners in criminal investigations conducted by the (US) military services were validated against unanimous guilt-innocence decisions by a panel of four Judge Advocate General (JAG) attorneys. Level of agreement was 92%.

Hants, C. R. (1996). The Journal of General Psychology, 123(4)-324.
Data from the files of 41 criminal cases were examined for confirming information and were rated by two evaluators on the strength of the confirming information. The decisions of the original examiners were correct 96% of the time, and the independent evaluators were 93% correct.

Patric, C. J., & Iacano, W. G. (1991). Journal of Applied Psychology, 76(2), 229-238.
Records from independent (Canadian) police files for 402 control question test (CQTs) conducted during a 5-year period by federal police examiners in a major Canadian city, the hit rate for identifying guilty subject was 98%.

Raskin, D. C., Kircher, J. C., Honts, C. R., & Horowitz, S. W. (1988).
Report to the National Institute of Justice. Polygraph charts from examinations conducted by the U.S. Secret Service were sampled and blindly interpreted by polygraph examiners and by computer interpretation using algorithms. Decisions by the original examiners on individual relevant questions ranged from 91-96% correct on confirmed truthful answers and 85-95% correct on confirmed deceptive answers.

I'm telling the truth, but I'm nervous about taking the examination. How does the instrument tell the difference between nervousness and lying?
It is quite normal for an innocent person to be nervous, and the Polygraph examiner (Psychophysiologist) is aware of this. A truthful person maybe nervous because he/she is afraid of the unknown. More importantly, nervousness on the Polygraph readings does not appear like deception to the Polygraph examiner, therefore does not prevent an examiner from distinguishing between truth and untruth.

I have high blood pressure. Would that look as though I'm lying?
While blood pressure is the principal Polygraph recording, it does not cause the characteristic pattern that results when a person is untruthful. An untruthful answer appears on Polygraph chart as a characteristic pattern different from that created by either high or low blood pressure. A truthful answer is readily apparent, even though a person has a blood pressure problem. If you are currently under treatment because of a heart condition or any mental condition, be sure to tell the polygraphist about it.

Does the test hurt? Will I get an electric shock?
No, the test does NOT hurt and there is NO possibility of you getting an electric shock. It is most important that during the examination you be as comfortable as possible. The only discomfort some people experience is a slight pressure on the arm because of the standard blood pressure cuff. This is the same kind of upper-arm cuff a doctor uses to determine your blood pressure, and it is generally no more uncomfortable than when a doctor takes your pressure. Other than that, there is no discomfort involved.

Suppose the instrument says I'm lying when I'm not?
The Polygraph cannot "say" anything. It merely records on a chart your bodily reactions to the questions you are being asked. It is up to the Polygraphist to "read" the information your body provides, and he does so with a high degree of accuracy.

I heard there would be questions about my sex habits?
Personal and intrusive questions have no place in a properly conducted Polygraph examination. Questions concerning your sex habits or preferences, beliefs or opinions regarding racial matters, political beliefs or affiliations, have no place in a Polygraph examination, unless you are accused of committing a sex crime and the purpose of the test is for you to prove your innocence.

Will I know beforehand what the test questions will be?
Yes. You will be told word for word the exact questions on the test and you will be asked only those questions you consent. The examination itself requires "yes" and "no" answers. The Polygraphist will discuss the questions with you and reword them if necessary until you can easily answer "yes" or "no" to each one. The test will not begin until you are comfortable with the questions.

Will there be a trick questions?
No. The Polygraph examiner is counting on your trust in him/her and your co-operation. The examiner cannot expect your trust or co-operation if they do something, which leads you to mistrust him/her. You will know the questions before the test begins. If you do not wish to have a certain question(s) asked, just let the Polygraphist know when he reads the questions to you before the test begins and they will not ask it.

I feel that a Polygraph Examination is an invasion of privacy.
A competent Psychophysiologist (Polygraph Examiner) is interested only in determining if you have been truthful about a particular statement. If you agree to be examined, it can hardly be termed as invasion of privacy. Of course, if you do not agree, no examination will be administered. A Polygraph examination cannot be administrated without the voluntary consent of the person being examined.

How long does Polygraph examination take?
Most examinations take approximately two and a half to three hours. This includes the pre-test interview, question formulation, introduction to the Polygraph instrument, Polygraph test itself and interpretation of charts. A re-examination is sometimes necessary.

What is a re-examination? Will I have to take one?
Polygraphist usually requests a re-examination when he cannot interpret the first Polygraph recordings. In most instances interpretable recordings are then obtained during the re-examination. Of course, we never know in advance whether or not a person will be asked to take a re-examination. Taking a re-examination is like taking the original examination. If you want it take it. Once again a re-examination must be voluntary.

If I take the Polygraph examination whose side is the Polygraphist going to be on?
Neither side. The aim of Polygraphist is to seek the truth. He must give careful attention to every person he is examining. Every person, whether truthful or not, has the right to be examined with dignity and impartiality.

How can I tell if the Polygraphist knows what he/she is doing?
This is probably the most important question you can ask before you consent to take a Polygraph examination. If you have read the proceeding questions and answers carefully, you know what is expected of a qualified ethical Polygraphist. If he/she departs from the above described standards, you should seriously question their professionalism. You would not consent to surgery by an unqualified doctor, so you should not consent to a Polygraph examination by an unqualified Polygraphist. There is a method of inquiring about the professionalism of the Polygraphist before the examination. Check your Polygraphist's reputation in the professional community. Find out if he/she is appropriately qualified by accredited institution to administer a polygraph examination. For example, be certain that he/she has had specific training/schooling to become a Polygraphist. Every professional Psychophisiologyst (Polygraph examiner) should be proud to present his/her professional credentials. There are professional societies with membership limited to the professional Polygraphist. Any professionally trained Forensic Psychophisiologyst (Polygraph examiner) should belong to a relevant professional body. The biggest and the most reputable is the American Polygraph Association, which through its Ethics and Grievance Committee, fairly and impartially investigates all allegations of misconduct against members of its Association. If a person claims or advertises that he/she is a Polygraph examiner, yet he/she cannot or does not want to produce the evidence of his professional training with accredited institution, and membership with a relevant association, do not consent to a Polygraph examination by that person.

FAQ from The Journal of Polygraph Studies, Volume IV, No.1, July-August,1969