What is a polygraph examination?

The polygraph technique involves the use of a scientific instrument to monitor, record, and display physiological responses to specified test questions.  The polygraph technique is also known as the Psychophysiological Detection of Deception (PDD).  This means that the polygraph instrument monitors, records, and displays how your body responds once your brain has interpreted the stimulus; in this case, the questions being asked during the examination.

From a psychological perspective, polygraph operates under the “fight or flight” response that all human beings have when they are presented with a threat.  For example, when our ancient ancestors came across a sabretooth tiger in the woods, they would either run or fight the animal.  In either case, the sympathetic nervous system triggers the body to send blood, sweat, and oxygen to various parts of the body to aid in fleeing or fighting.  Once the threat is over, the parasympathetic nervous system returns the body to its normal level of functioning.  While we no longer live in a world in which we need to fear sabretooth tigers, our body still operates in the same way when presented with a threat.  In polygraph, that threat stems from the fact that we know that we are lying to a particular question and the polygraph instrument monitors, records, and displays the physiological responses to that threat.

What is recorded during a polygraph examination?

The onset of the sympathetic and parasympathetic nervous systems are recorded by the various components that comprise a polygraph instrument.

  • Pneumograph tubes are placed around the stomach and upper chest to monitor and record internal body movements associated with breathing.
  • Electrodermal Activity (EDA) plates are placed on the fingers or palms to monitor and record changes in sweat gland activity.
  • A cardio cuff is placed on the arm to monitor and record changes in pulse rate and relative blood pressure.
  • Movement sensors are placed on the seat of the chair and under the feet to detect body movements.

Whose side is the polygraph examiner on?

Your polygraph examiner at Federal Polygraph Investigations (FPI) is an independent and neutral party who is being requested to identify whether the subject of the examination is telling the truth.  Being that FPI has been founded on the principles of fairness, professionalism, and integrity, your FPI polygraph examiner will remain neutral and unbiased in administering the examination regardless of who is requesting the examination or paying for its administration.

Can a person be forced to take a polygraph examination?

No.  A polygraph examination requires the examinee to be cooperative and they must voluntarily submit to the examination of their own free will.  Prior to being administered a polygraph examination at Federal Polygraph Investigations (FPI), the examinee will be required to affirm that they are taking the test voluntarily.

Is a polygraph examination painful?

No.  While the components of a polygraph instrument may look scary, they do not cause pain.  Some examinees may complain that the cardio cuff (the same type of cuff utilized in a doctor’s office to check blood pressure) may feel snug.  However, modern computerized polygraph instruments use less pressure than previous analog instruments.  In addition, the pressure will only remain in the cuff during each asking of the questions.  After each asking, the pressure is immediately removed and the examinee is given a brief break.  As a result, complaints about discomfort during the course of an examination are rare.

How long is a polygraph examination?

While the length of the polygraph examination depends on the complexity of the specific matter, you can anticipate that your polygraph examination at Federal Polygraph Investigations (FPI) will take roughly 2-3 hours.  This will include the pre-test interview, the actual examination, an analysis of the test data, and a post-test interview.

How many questions will be on the polygraph examination?

The number of questions on the polygraph examination will ultimately depend on the specific testing format that will be utilized in your unique situation.  While you can anticipate that between 2 and 4 questions relating to your specific issue will be asked, several other technical questions will also be asked.  In general, your examination will include approximately 10 questions.

The final questions will be based on the answers given by the examinee during the pre-test interview and will be worded based on the examinee’s understanding.  There are no trick or surprise questions and the examinee will know the wording and meaning of each question before the examination is initiated.

Can nervousness impact my examination?

No.  There is no evidence to suggest that anxiety or nervousness alone will cause truthful examinees to fail their examination.  It is normal for a person to feel nervous prior to and during a polygraph examination.  When a person gets nervous, they may experience an elevated heart rate, increased blood pressure, or other changes in their physiology.  Your FPI polygraph examiner is not only aware of this likelihood, but they will administer you a practice examination prior to your test to establish your physiological baseline at the time of the examination.  This will be considered your normal physiological functioning at that time.  During the actual examination, your examiner will look for deviations from that baseline.

How should I prepare for my examination?

It is necessary for the examinee to be suitable for testing at the time of the examination.  This means that you should do the following:

  • Ensure that you get a proper night’s sleep
  • Refrain from consuming alcohol or illegal drugs within 24 hours of the examination
  • Take your prescribed medication as you normally would
  • Ensure that you have a light breakfast and/or lunch depending on the time of your examination
  • Wear comfortable business casual clothing on the day of your examination. Since the polygraph components will be placed over your clothing, refrain from wearing bulky sweaters or sweatshirts to ensure that the components can properly record your physiology.
  • Avoid taking the examination if you are sick. If you are not feeling well on the day of your examination, contact Federal Polygraph Investigations (FPI) to reschedule your examination.

Can I bring a friend or family member with me for my test?

During the examination, only you and the examiner are permitted in the polygraph room.  In addition, due to the anticipated length of the examination and the layout of the Federal Polygraph Investigations (FPI) office, it is not possible for your friends or family members to wait for you within the office.  If you require a ride to the FPI office, please make your friend or family member aware that they will not be permitted to wait in the office, but you will immediately call them at the end of the examination so that you can be picked up.

Can a person “beat” a polygraph test?

At times, a person may obtain information from a friend or on a website that they believe will help them to pass a polygraph test when they know that they are being dishonest.  However, in light of the extremely sophisticated components of the polygraph instrument, these attempts to “beat” a polygraph test routinely become immediately apparent.  Ultimately, this causes the examinee to look guilty.  The same holds true for examinees who are telling the truth, but engage in these same behaviors to help the polygraph instrument identify their truthfulness.  As such, it is highly recommended that a person seeking an examination from Federal Polygraph Investigations (FPI) avoid researching methods to “beat” a polygraph test and refrain from using such methods during the course of the examination.

How long will it take to get my polygraph results?

Once the polygraph examination is completed, the polygraph examiner will evaluate the data provided.  Under most circumstances, the examinee will be verbally provided the polygraph results that same day.  A written report documenting the final results of the examination will also be provided once generated.

It is important to note that the results of your polygraph examination are considered confidential.  These results will not be discussed or shared with anyone other than those individuals whom you specify in your written agreement signed prior to the examination.

What is the Employee Polygraph Protection Act (EPPA)?

The Employee Polygraph Protection Act (EPPA) generally precludes most non-government employers from requiring prospective employees or onboard employees to take a polygraph examination as a requirement for employment.  To learn more about the EPPA, please click on the link below:


Are polygraph examination results admissible in court?

In general, the results of a polygraph examination are not admissible in court.  However, the results of an examination can sometimes be admitted as evidence in some jurisdictions when both the prosecutor and the defense attorney agree to this arrangement prior to the polygraph being administered.  Many jurisdictions allow a party to seek the admission of a polygraph examination as evidence on a case-by-case basis.

How accurate is the polygraph technique?

According to the U.S. National Research Council, the median accuracy rate for polygraph examinations administered on single issues or event-specific testing is between 85% and 90%.  Additional research into empirically-derived polygraph practices determined the polygraph accuracy rate as greater than 90%.  When a qualified polygraph examiner administers the examination in accordance with prescribed methods, U.S. Government research has estimated the polygraph accuracy rate to be 87% – 95%.  Some private academic researchers have suggested that the polygraph accuracy rate can be as high as 95% – 98%.

Regardless of the stated statistic, these researchers make it clear that the accuracy of the polygraph technique increases when an experienced polygraph examiner administers an industry-approved testing format.  With Federal Polygraph Investigations (FPI), you can be assured that the polygraph test you receive will be administered by a former certified polygraph examiner of the Federal Bureau of Investigation (FBI) and graduate of the U.S. government’s premier federal polygraph school.  No other examiner in the State of Michigan offers this level of knowledge, training, and experience.

How much does a polygraph test cost?

Typically, polygraph tests range between $500 and $1,000.  It is important to note that when it comes to polygraph testing, like most things in life, you get what you pay for.  In your unique situation, you must identify whether you want to rely on the lowest bidder or the most highly-trained and experienced polygraph professional with an outstanding name and reputation.  To help you in this monumental decision, please call Federal Polygraph Investigations (FPI) for a free consultation and quote.

If you decide to seek the services of FPI, please be mindful that your payment will be collected prior to the administration of your polygraph examination.  This prevents any appearance of impropriety and counteracts any claims that your examination was unduly influenced by financial payment.