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Selecting an Investigator

There are thousands of licensed investigators, but few have experience with employment law, employee misconduct, financial matters or forensic psychophysiological detection of deception. Certified Fraud Examiners (CFE) may have some experience with financial matters but may lack experience with employment or investigative techniques and interviewing.

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Selecting a Polygraph Examiner

At Professional Litigation & Polygraph Services, LLC, we provide our clients with results at a fair price utilizing legal and accepted ethical practices and conduct.

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Best Practices

Polygraph - Frequently Asked Questions

What is a polygraph?
What does a polygraph examination consist of?
Are there errors in polygraph examinations?
Who should take a polygraph test?
What are "countermeasures"?
How old does someone have to be?
Will a medical condition affect the examination?
Can a pregnant woman undergo a polygraph examination?
Does a person'a high blood pressure affect the polygraph test?
Will drugs or alcohol affect the accuracy of a polygraph test?
What affect does being nervous have on the exam?
How long does a polygraph examination take?
What questions will be asked of me during a polygraph exam?
How many issues can I be asked about?
Why does the examination cost so much?
Are the polygraph results admissible in court?
Is the polygraph confidential?
Do I get the results of my test?
Should someone prepare for an examination?
What should I look for when hiring an examiner?
What is the Employee Polygraph Protection Act?
Can a polygraph be required for employment?
How do I get a polygraph examination done?
What is Computerized Voice Stress Analysis (CVSA)?
Do you offer other services?
Are a list of references available?


What is a polygraph?

The term "polygraph" translates to "many writings." The name refers to the manner in which selected physiological activities are simultaneously recorded. The polygraph measures predictable changes in a person’s body that are associated with the stress of deception. These changes include alterations in heart rate, breathing, and electrodermal activity (emotional sweating). Many other changes occur as well: the pupils get larger, digestion slows, the body’s blood supply is redistributed away from the skin and gastrointestinal regions and toward the muscles, etc. The measures used by the polygraph were found early on to be simple to record, they were sensitive (even minor changes in stress levels caused physiological changes to occur), and they are accurate.

What does a polygraph examination consist of?

A polygraph instrument will collect physiological data from at least three systems in the human body. Typically, convoluted rubber tubes that are placed over the examinee's chest and abdominal area will record thoracic activity. Two small pads are attached to the fingers or palm that will record changes in skin sensitivity caused by a light sweating of the hands, and a blood pressure cuff will record cardiovascular activity.

A typical polygraph examination will include a period referred to as a pre-test, physiological monitoring phase and an analysis phase.

In the pre-test, the polygraph examiner will complete required paperwork and talk with the examinee about the testing process and the information surrounding the issue(s) to be resolved. During this period, the examiner will discuss the questions to be asked and familiarize the examinee with the testing procedure.

During the chart physiological monitoring phase, the examiner will administer and collect several polygraph charts for analysis. Following this, the examiner will analyze the charts and render an opinion as to the truthfulness of the person undergoing the examination.

The examiner will offer the examinee an opportunity to explain physiological responses in relation to one or more questions asked during the examination.

Are there errors in polygraph examinations?
(False Positive, False Negative)

Today, polygraph testing remains the most accurate means of developing and verifying the truth and detecting deception. Published just this year, the Department of Defense’s analyses of the validity and reliability from data collected from either live or actual tests and mock or laboratory tests reveal the accuracy is an amazing 98%. While the polygraph technique is highly accurate, errors can occur. Errors may be caused by the examiner's failure to properly prepare the examinee for the examination, or by a misreading of the physiological data on the charts obtained. U.S. Government studies have concluded that the single-issue (one question) polygraph exam, conducted properly by a qualified examiner, is most accurate. 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.

Errors are usually referred to as either false positives or false negatives. A false positive occurs when a truthful examinee is reported as being deceptive; a false negative when a deceptive examinee is reported as truthful. Research indicates that false negatives occur more frequently than false positives; however, other research studies show the opposite conclusion.

Since any error is damaging, examiners utilize a variety of procedures to identify the presence of factors which may cause false responses, and to insure an unbiased review of the polygraph records:

Protective Procedures:
  • an assessment of the examinee's emotional state
  • medical information about the examinee's physical condition
  • specialized tests to identify the overly responsive examinee and to calm the overly nervous
  • control questions to evaluate the examinee's response capabilities
  • factual analysis of the case information
  • a pre-test interview and detailed review of the questions
  • quality control reviews
Examinee's Remedies
If an examinee believes that an error has occurred, there are several remedies available to include the following:
  • request a second examination
  • retain an independent examiner for a second opinion
  • file a complaint with a state licensing board
  • file a complaint with the Department of Labor (EPPA examinations)
  • file a request for the assistance of the American Polygraph Association

Who should take a polygraph test?

Any person who desires to verify their truthfulness regarding a specific situation or incident. Any person who intends to lie or withhold any relevant information about the issue under consideration should avoid the process.

What are "countermeasures"?

The unauthorized and undisclosed use of drugs, alcohol, subtle movements, self induced pain or conflict and mental gymnastics are all considered countermeasures. Countermeasures do not help an examinee taking a polygraph change the final result. Instead, competent well-trained polygraph examiners are trained to look for the tell tale indicators of attempts to alter the appearance normal physiological activity in the body, which makes for a conclusive finding of deception.

How old does someone have to be?

Depending upon the mental age, subjects over the age of 12 can be examined. The examiner must first have written consent of a parent or guardian.

Will a medical condition affect the examination?

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 and is typically inflated for less than six 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, an approval from the treating physician prior to conducting an exam on someone may be recommended.

Can a pregnant woman undergo a polygraph examination?

Pregnancy does not affect the outcome of a polygraph exam unless the fetus is making excessive movements or causing pain to the mother. As a standard practice, for liability reasons only, we do not examine a pregnant woman. Exceptions have been made in the past as long as the mother knows and waives any liability on the part of the examiner and Professional Litigation & Polygraph Services, LLC. If an examination is required, a note from the woman's physician stating that there are no complications from the pregnancy and that the stress of undergoing a polygraph would not impact the health of the mother or fetus may be required prior to the examination.

Does a person's high blood pressure affect the polygraph test?

Not usually. While blood pressure is one of the physiological reactions measured, it does not affect the accuracy of the test.

Will drugs or alcohol affect the accuracy of a polygraph test?

The use of drugs and/or alcohol will not assist someone to beat a polygraph test. Polygraph examiners utilize certain procedures during the examination to ensure that each person undergoing an examination is responding naturally throughout the testing procedure. If you are taking any medication you need to inform the polygraph examiner prior to beginning the test. Physiological affects that drugs have on people are immediately seen in polygraph chart tracings. Irregular physiological recordings must be satisfactorily explained.

What affect does being nervous have on the exam?

Everyone who submits to a polygraph is nervous but for many different reasons. The polygraph instrument measures changes in a person's physiology during the course of the test. Nervousness is a generalized condition which exists throughout the entire exam, not just on one or two questions. Because nervousness exists during the entire test process, it will not affect the test score. Extreme nervousness, however, may cause a person to fidget or not sit still during the exam, and this could distort the test enough so that the results can not be analyzed. In general, though, being nervous will not change a person's test results. Most people are nervous when doing anything new for the first time.

Innocent:
Although most truthful persons believe they should pass a polygraph test, they are often worried that something might go wrong. This doubt will cause the person taking the test to experience a heightened sense of anxiety about the test itself. This kind of nervousness is normal and has no effect on the positive outcome.

Guilty:
Guilty persons are nervous also, but for a very different reason. The guilty tend to be afraid they are about to be exposed. When a guilty person’s bad actions are exposed, that guilty person will frequently suffer some negative consequence as a result of having done a bad thing. Being nervous about being exposed or about being punished for having done something wrong is also normal but it tends to help expose the guilty and deceptive.

How long does a polygraph examination take?

A professionally administered polygraph examination should normally take around 3 hours to properly administer from start to finish. A professional examiner will go through several structured test phases to ensure that it will work accurately. During the different phases the examiner and the person taking the test will become very involved in discussing the details of the test and the manner in which the questions are presented. Examinees often feel the need to fully explain their circumstances during the pretest. This is not discouraged by the examiner. The examiner will also attempt to answer each question presented to them by the examinee.

What questions will be asked of me during a polygraph exam?

Each and every question to be asked a person undergoing an examination is discussed in detail with that person in the pretest phase prior to the physiological monitoring portion where test charts are obtained. No professional polygraph examiner will ask a surprise or trick question during the monitoring phase. It is not only unethical for an examiner to ask a surprise question but responses to these types of questions do not accurately indicate truthful/non-truthful results.

Test Questions:

  • Are limited to "Yes" or "No" answers
  • Must have definitive objective answers and may not be opinions
  • Must relate to past events of a factual nature
  • Wording of questions must only have one interpretation
  • In the same exam must be related to one another. If distinctly separate issue types must be covered, they must be asked in separate examinations.

How many issues can I be asked about?

The most accurate test which can be conducted is the single issue test. If more issues must be explored, more questions must be asked and another exam must be designed and conducted following the first one. This usually adds to the time and cost involved. An effect called "anti-climax dampening" makes test results less reliable with an increase in the number of relevant test questions. A healthy individual can only produce readable polygraph charts for a limited period of time. After this time has expired, it is not possible to generate a conclusive polygraph test and any further testing must be scheduled for a different day.

Why does the examination cost so much?

Polygraph examiners are highly trained professionals, most with college degrees, who provide a very specialized service. This service requires the examiner to purchase expensive equipment and pursue continuing education in order to maintain a high degree of proficiency and licensing. The process of asking "just one question" could take hours, due to the diagnostic process involved, so a single exam often takes an examiner an entire working day (including travel). In most cases, the polygraph is performed because there simply is no other reasonable way to get the desired information, such as when there is no evidence one way or the other, or when it is simply a "he-said-she-said" situation. For example, a person might spend thousands of dollars on surveillance, investigation and other investigative means while the same information could be obtained for a fraction of the price with polygraph, resulting in thousands of dollars saved. The fees charged for polygraph testing are reasonable when considering the cost of training and equipment, degree of specialization and worldwide need for this unusual service.

Are the polygraph results admissible in court?

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. 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. In most cases, polygraph evidence is used during pre-trial negotiations and plea bargain agreements rather than during the trial itself. For more information go to www.polygraph.org.

Is the polygraph exam confidential?

Yes. The examiner works for and reports directly to you, the client. The examiner must decline any exams when a known conflict of interest exists. Admissions of criminal conduct are not revealed to anyone except the client unless authorized under the Employee Polygraph Protection Act.

Do I get the results of my test?

In each case a polygraph examiner should always tell the examinee the results. In cases where examinee has a problem with a question, the examiner should bring that problem question to the attention of the person taking the test so as to give them a specific opportunity to resolve that problem.

Should someone prepare for an examination?

For best results, a person taking a polygraph should be well-rested and free of any extraordinary fatigue or stress factors on the day of the exam. This means getting a good night's rest, eating normally, and avoiding stressful incidents (arguments, interrogations, emergencies) prior to the exam. We suggest postponing the examination until the cause of any physical pain has been remedied, rather than attempting to control the pain with medication. If the examinee is taking regular prescription medications he/she should continue taking those medications as prescribed. If the prescription medications are taken infrequently "as needed" then we generally advise not to take these medications until after the exam. Aspirin or other mild over-the-counter medications should have no affect on the exam.

What should I look for when hiring an examiner?

Make sure the examiner has a current license if it is needed in the state where the examination is to take place. The examiner has been "certified." Every examiner must attend a polygraph training program, preferably one certified by the American Polygraph Association. After graduation, the examiner must conduct a certain number of exams during an "internship" period. After the internship, the school reviews the examiner's work and grants the certification if this work was done to standards. After certification, most examiners must complete a certain amount of continuing education or advanced training programs. Be aware of an examiner who's been operating for 25 years but has not undergone regular advanced training. Technology changes and examiners must keep current. Look for professional affiliations and membership, such as the American Polygraph Association or other similar groups which set professional standards for examiners. Make sure the examiner has experience with the type of exam you need.

What is the Employee Polygraph Protection Act?

The Employee Polygraph Protection Act of 1988, (EPPA) is a federal law that was passed to ensure that an employee’s rights would be protected during a polygraph situation and to develop the terms under which most employees could be polygraph tested. This law is a good law so far as it goes to establish reasonable circumstances under which employees may be examined.

Polygraph examiners who do employment related examinations must be very familiar with this law and follow the law to the letter. Fines and punishments which are given to those business and examiners who intentionally violate the EPPA are substantial. Employees who are asked to take an employment related polygraph test should be provided a copy of their rights under the Employment Polygraph Protection Act by the test requestor or the examiner.

Can a polygraph be required for employment?

One exemption to the Employee Polygraph Protection Act allows for pre-employment screening and in some cases, periodic polygraph screening of employees. There are questions that are allowed and others that are not allowed to be asked or covered. No examiner should inquire into any of the following areas during pre-employment or periodic employment examinations:

  • religious or affiliations beliefs
  • opinions regarding racial matters, political beliefs or affiliations beliefs, affiliations
  • lawful activities regarding unions or labor organizations
  • sexual preferences or activities

In a law enforcement pre-employment polygraph examination, the questions are based upon the job description for the position applied for and focus on such job related inquiries as the theft of money or merchandise from previous employers, falsification of information on the job applications, the use of illegal drugs during working hours and other criminal activities.

The test questions are limited in the time span they cover, and all are reviewed and discussed with the examinee during a pre-test interview before any polygraph testing is done. There are no surprise or trick questions. If information exists that needs to be verified, a specific issue polygraph examination is developed using relevant questions that focus on a particular act in question.

How do I get a polygraph examination done?

Contact us by e-mail or calling us. We will need payment in cash or certified check before the examination and in some cases, a deposit will be needed before we will schedule the appointment. The examiner will contact you to schedule your appointment for a mutually convenient date and time. Any balance of the test fee is paid directly to the examiner prior to the examination.

What is Computerized Voice Stress Analysis (CVSA)?

Starting about 30 years ago, serious efforts were made to use the voice to detect deception. Many devices were marketed for this purpose. The most widely advertised devices have been the Psychological Stress Evaluator (PSE), the Hagoth, the Mark II Voice Stress Analyzer (VSA), and the Computerized Voice Stress Analyzer (CVSA). If effective, voice analysis offers many advantages over current polygraph methodology. Voice samples can be recorded without discomfort to the subject. Examinations could be conducted remotely, both in distance, using a telephone or radio link, or in time, using a tape recording. In rare cases, it could even be conducted after a person’s death, if a recording made under proper technical, psychological, and investigative conditions existed. The recordings could also be conducted surreptitiously. However, CVSA is not and should not be associated with polygraph testing in any way. The preponderance of evidence indicates the polygraph is far more accurate at detecting deception than voice stress analysis. No Department of Defense agency uses any form of voice stress analysis for investigative purposes. There is no known published scientific research study that confirms voice stress tests provide results any better than chance (the flip of a coin). Go to www.polygraph.org to review the latest information concerning CVSA.

Do you offer other services?

A general list of our services can be viewed under Investigations. We have extensive experience in the area of criminal and civil investigations, trial investigation defense preparation, strategy and consultation, witness coordination, forensic consulting, accident analysis and reconstruction, background investigations, witness location, surveillance, interview and interrogation, commercial loss investigation and commercial employee wrong doing.

Are a list of references available?

A list of references will be provided upon request.