Any consideration of polygraph testing should begin with the realization that polygraph examinations are a serious matter.  They are not a game or something to experience, just to say you did it.  Therefore, you should understand why it is that you are taking the examination, as well as how the outcome will affect you.  In the United States, there are two primary reasons a person would be asked to take a polygraph exam.

Many organizations utilize the polygraph as part of an investigation regarding some specific event.  (Notice that we say “part of”.  The polygraph is used as an investigative or forensic tool.  Seldom is it or should it be the entire investigation.)  The majority of federal, state and municipal law enforcement agencies in the United States use polygraph to support investigation of criminal matters.  A suspect or person of interest, who denies involvement in the matter under investigation, may be asked to take a polygraph examination as a means of assessing his or her denials.  A witness or informant may be asked to submit to a polygraph for the purpose of assessing the information he or she has provided.  In some cases, even a victim of crime may be asked to demonstrate veracity to prevent the wrongful prosecution of an innocent person.  In addition to law enforcement agencies, many businesses such as insurance companies, auditing firms and financial institutions utilize the polygraph as an investigative tool.  Because attorneys regularly deal with controversial matters, they often turn to the polygraph to assist their efforts, too.

The second common use of the polygraph is in the support of security and personnel screening programs.  Many law enforcement agencies such as municipal police departments, state police and federal agencies, such as the Federal Bureau of Investigation and United States Secret Service utilize the polygraph as a component of their personnel screening process.  The objective is to enhance the probability that the individuals selected for these positions of trust will be of high integrity.  Many agencies of the United States Intelligence community utilize polygraph testing as one component in their security clearance process.  Some include the polygraph as part of the initial selection methods.  Others use it as part of ongoing security maintenance, and some use it for both purposes.


Each type of examination, the specific investigation and the screening exam, has different characteristics and features.  The potential impact on the examinee is also very different.  Therefore, if you consider taking a polygraph examination, you should understand the type of exam you will be administered and the possible impact on your personal circumstances.  In some cases a person may receive a positive benefit from the examination, while in other circumstances the potential negative impact can be very significant.  A person should know how the polygraph examination is likely to affect them before she or he agrees to undergo the process.  This means an individual should have a good idea as to the issue(s) or subject matter of the exam.  The person should assess his or her ability and willingness to be thorough and truthful regarding the issue(s) of the exam.

Suppose a law enforcement agency asked you to submit to a polygraph examination because you are a suspect or person of interest in a particular crime.  The APA encourages citizens to cooperate with law enforcement agencies.  However, be aware that if you are involved in the matter under investigation and have concealed that fact from investigators, your deception will almost certainly be identified.  If you have committed the crime you might want to seek legal counsel before proceeding with the polygraph.  If you have not been involved in the matter under investigation, there probably are very strong reasons for you to proceed with the examination.  Nevertheless, it is wise to confirm the issue(s) of the exam in advance.  It is also a good idea to obtain some assurances as to how the polygraph results will be utilized.  Will truthful results significantly lower you on the suspect list?  What is the benefit or payoff to you for the time and effort of submitting to the exam?  Similar questions should be addressed with entities such as an employer or an insurance company that might request that you submit to polygraph testing.

If your attorney is advising that you take the polygraph examination, you probably do not need to concern yourself with such issues.  Generally, it is the responsibility of legal counsel to ensure your interests are protected.  However, you should have an understanding as to the primary issue of the exam so you can review the matter with your counsel in advance.

You may also be offered a polygraph examination in relation to a job application or federal security clearance.  Such exams are referred to as screening exams.  Screening exams are different in several ways from the specific issue exam.  First, screening exams address several issues as opposed to a specific matter of investigation.  Secondly, the issues of a screening exam tend to be broad in scope and cover a variety of possible activities.  For example, a law enforcement agency may use the exam to address issues such as major thefts/fraud, physical abuse of others, and illegal drug use.

If you decide to submit to the screening polygraph examination, you are encouraged to consider to the following advice.  First be aware that exams may be long (3-4 hours).  It is very important that you remain alert and involved for the entire session.  So, prior to the exam get a good night’s sleep and arrive well rested for the procedure.  Be sure to eat a meal, and take care of personal affairs so you won’t have any outside distractions during the time of your examination.  If you are using a medication, adhere to your normal practice and physician’s advice.  Most medications are used to maintain an individual’s good health, which is desirable for polygraph testing.  Expect to experience some nervousness: this is normal for everyone.  Contrary to a common misperception, nervousness and anxiety will not cause a person to “fail” the test.  Moreover, truthful examinees generally report that they become much less nervous as the examination proceeds.

The term “polygraph” or commonly known as a “Lie Detector” literally means “many writings.” The name refers to the manner in which selected physiological activities are simultaneously recorded. Polygraph examiners may use conventional instruments, sometimes referred to as analog instruments, or computerized polygraph instruments.
It is important to understand what a polygraph examination entails. A polygraph instrument will collect physiological data from at least three systems in the human body. Convoluted rubber tubes that are placed over the examinee’s chest and abdominal area will record respiratory activity. Two small metal plates, attached to the fingers, will record sweat gland activity, and a blood pressure cuff, or similar device will record cardiovascular activity.



A typical polygraph examination will include a period referred to as a pre-test, a chart collection phase and a test data analysis phase. In the pre-test, the polygraph examiner will complete required paperwork and talk with the examinee about the test. During this period, the examiner will discuss the questions to be asked and familiarize the examinee with the testing procedure. During the chart collection phase, the examiner will administer and collect a number of polygraph charts.

Following this, the examiner will analyze the charts and render an opinion as to the truthfulness of the person taking the test. The examiner, when appropriate, will offer the examinee 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 include the analysis of physiology associated with the voice. Instruments that claim to record voice stress are not polygraphs and have not been shown to have scientific support.


Three sectors of society use polygraph examinations for various reasons and purposes.

Private Sector
Individuals, Families, Therapists and Employers use polygraph examinations to verify statements and find out the truth on a variety of issues including infidelity, drug use, addictions, sex offenses, employee theft, criminal activities, abuse and all other matters.

Legal Community
Polygraph is used extensively by attorneys who wish to provide the best possible defense for their clients. Most attorneys will submit their own clients to the exam, while others will use the polygraph to verify statements made by witnesses and other parties to litigation. Now known as Psycho physiological Detection of Deception (PDD), an experienced examiner can provide evidence in connection with any type of criminal or civil matter. Our examiners have a great deal of experience working with attorneys, both in private and government practice, and have aided thousands of clients in preparing defenses that would otherwise have been unavailable to them. With the recent establishment of polygraph standards by ASTM, polygraph has gained great strides in credibility with the scientific community. These standards, approved by a combined body of experts, now provide a template for the increased acceptability of polygraph results.

Contrary to popular belief, polygraph is not per-se inadmissible in court proceedings. Admissibility standards are different in each jurisdiction. Some jurisdictions allow polygraph evidence, either stipulated or un-stipulated, some prohibit polygraph evidence altogether, and many others allow the judge to decide admissibility on a case-by-case basis. The Daubert case is presently the standard for the admission of scientific evidence, which includes polygraph. In reality, most polygraph results are used outside of the courtroom in pre-trial negotiations, plea bargaining, sentence recommendations, and witness verification or impeachment.

Law Enforcement, Federal Agencies, Military and Government

Local Police, U.S. Military Branches and Government Agencies such as the FBI, CIA, NSA and Department of Defense all use polygraph examinations for applicant screenings, criminal investigations and matters of national security.


U.S. Government studies have concluded that the single-issue (one question) polygraph exam, conducted properly by a qualified examiner, is 87 to 95 percent accurate.  It is the most accurate tool available today for determining truth or deception.  Accuracy of the multi-question exam drops to around 80 percent due to a number of psychological factors.  These statistics do not include “inconclusive” results in which no opinion can be made from the polygraph charts, which happens about 20% of the time.

While the polygraph technique is not infallible, research clearly indicates that when administered by a competent examiner, the polygraph test is one of the most accurate means available to determine truth and deception.
For an excellent review of the research involving validity and reliability, including pre-employment screening, see: The Accuracy and Utility; of Polygraph Testing. (1984) Washington, DC: U.S. Department of Defense, 1984. Complete reprints may be purchased from the APA National Office.


A polygraph exam does not cause any direct injury to the person being tested. The only discomfort is a standard blood pressure cuff which goes on the arm (typically) and is inflated for less than five minutes at a time. There are increased stress levels during the testing process which should be considered. Some medical conditions are sensitive to increased stress levels, such as some heart conditions. Depending on the medical condition, most examiners would require an approval from the treating physician prior to conducting an exam on someone with such a condition.


No. Polygraph is not designed to record or measure nervousness. While a person’s heart beat and respiration rate may increase when he or she is nervous, a qualified examiner understands this, and will take it into consideration when evaluating an examinee’s response. Unlike general nervous tension, an examinee’s reaction to deceptive responses is highly specific. An examiner mitigates a nervous response by reviewing the questions with the examinee and through an acquaintance or “practice test” prior to the exam.

The polygraph works by recording changes in a person’s Sympathetic Nervous System, part of the Autonomic Nervous System, which operates independently of conscious thought. For example, your lungs and heart continue to operate even when you are asleep – you don’t have to think about it. These systems can be consciously controlled only very slightly, and attempts to change these systems are usually picked up by the examiners, who are trained to identify such things. It is highly unlikely that someone can alter the outcome of a polygraph exam, but it is not impossible. A verified accuracy rate as high as 95% attests to this fact.


Federal courts have ruled that polygraph is NOT per-se inadmissible in a court procedure, but that it may be considered when standard rules of scientific evidence have been met. In other words, applicants must apply to the judge for admissibility under the “Daubert” standard of evidence on a case-by-case basis. Individual judges can still decline to accept polygraph results, however. Each jurisdiction must be checked to determine admissibility standards. One of the greatest fears keeping polygraph evidence out of courts is the fact that such evidence would carry greater weight than other equally-important evidence and would tend to sway a jury in one direction even though other evidence may point the other way. In most cases, polygraph evidence is used during pre-trial negotiations and plea bargain agreements rather than during the trial itself.

When a polygraph examiner concludes that deception is indicated to one or more of the subject’s answers, the subject is said to have “failed” the exam.  Deception is indicated when the person’s autonomic nervous system displays a significant and repetitive “defensive” reaction to the relevant test question.  Although this reaction in itself is not a “lie,” years of research have found that 90-95% of persons who display this reaction were either lying to the relevant questions or were withholding pertinent information relating to these question.  Frequently, an examiner will conclude only that “the subject can not be excluded as a suspect” when deceptive reactions are present.  It is important to note that some persons will “fail” a polygraph even though they are telling the literal truth but continue to hold back pertinent or incriminating information from the examiner.   We strongly suggest that no one make a life-altering decision based solely on the results of a “failed” polygraph test without the existence of additional evidence supporting this test result.


Licensing – Currently there are 29 states and 3 counties which have laws requiring licensure or certification for polygraph examiners. Most laws require formal instruction, an internship training period and successful completion of a licensing examination. For example, the following are basic requirements for licensure in one state:

A person is qualified to receive a license as an examiner:
(a) Who establishes that he or she is a person of good moral character; and,

(b) Who has passed an examination conducted by the Licensing Committee, or under its supervision? To determine his or her competency to obtain a license to practice as an examiner and

(c) Who has conferred upon him or her an academic degree, at the baccalaureate level, from an accredited college or university; and,

(d) Who has satisfactorily completed 6 months of study in the detection of deception, as prescribed by rule.

Holland Polygraph Services adheres to very strict confidentiality and privacy standards. All information from an examination is kept strictly confidential and private.