Make sure the examiner has attended and graduated from an accredited polygraph training school. The American Polygraph Association is currently the only accrediting organization for these schools and assures that the schools meet a minimum standard for instruction of primary polygraph students. Dont hesitate to contact the school and/or the APA for verification. All GPN examiners have completed training at accredited polygraph schools.
Make sure the person you plan to hire has sufficient experience. The more polygraph experience an examiner has, both in terms of years in the business and number of total exams, the more likely it is that this examiner can deal with any situation or resolve a difficult testing issue. All GPN examiners must complete a specified number of exams to qualify for membership. We do not refer examiners who have just completed polygraph school.
Type of Experience
Some examiners have lots of overall experience, but not so much with the type of case you are presenting. Make sure the examiner has experience with your type of case. All GPN examiners are experienced in a wide variety of testing situations.
Even though an examiner have many years of overall experience, if he/she is not currently testing on a regular basis that examiner's skills will not be as sharp as someone who provides frequent tests. All GPN examiners are actively in the business of providing polygraph testing. We do not accept applications from examiners who only provide polygraphs as a hobby or sideline.
Technology evolves. Polygraph techniques and equipment are updated often, so
even though an examiner may have a great deal of experience, if they are not
using the latest techniques and validated testing formats the test will be substandard
and will not stand up to expert scrutiny. All GPN examiners are required to maintain
continuing (advanced) polygraph education.
The only way to stay current in this profession is
to belong to a professional organization that sets membership requirements,
establishes certification criteria, and provides continuing education opportunities.
There are only four credible national organizations: American Polygraph Association
(APA), American Association of Police Polygraphists (AAPP), National Polygraph
Association (NPA), and the Global Polygraph Network (GPN). We do not recommend
hiring an examiner who does not belong to at least TWO of the above organizations.
half of the U.S. states require polyraph examiners to be licensed. If your exam
is to take place in one of these states, you should make sure that the examiner
is properly licensed. If a license is required, GPN has already insured that
your examiner holds such a license. If an examiner is operating in a non-licensing
state or country, it is not possible for the examiner to possess or obtain a
license in that state or country. You may locate your U.S. state licensing board
by visiting our links page and clicking on "State Polygraph Licensing Boards."
Quality Control (QC)
stand behind their work and should allow you to get a second opinion
if you want one. All GPN examiners must provide a complete set of charts (polygrams)
from your polygraph upon request so you can have them reviewed by another
examiner (note that a qualified QC examiner must have completed training at
an APA-accredited training facility and must be specifically trained in the
technique used by your GPN examiner). You should avoid hiring any examiner
who is not willing to release his/her work product for QC review.
Be sure the examiner is using fully-operational equipment. Some examiners try to get by with poorly maintained instruments, with some units barely working at all. Ask the examiner if all the recording channels on his/her polygraph are fully functional. If it is analog equipment, ask how often this equipment is calibrated. If computerized equipment is used, ask if the examiner is using the latest software version available. All GPN examiners maintain their equipment to the highest of standards.
There is a great deal of literature available regarding countermeasures, or how to beat the polygraph. A quality examiner will have training to easily identify when a person is attempting these techniques. Many examiners also use CM detection monitors to help them catch people who attempt to alter their test results. Ask your examiner if he/she uses such equipment.
If you intend to use the polygraph results as evidence, you should select an examiner who has testified and been approved as an expert to present polygraph evidence in court.
Number of questions allowed
Generally speaking, the more relevant questions asked in a polygraph exam the less accurate the results will be. A single-question test is the most accurate exam you can get. Many examiners will allow 3 or 4 questions to be asked in an exam as long as all these questions are on the same general topic. If an examiner tells you that he/she can ask 10 or more questions on an exam, you will be getting what is called a screening test, not a true polygraph. The results of a screening test can not be relied on and must be verified by running a separate exam on each relevant question.
Do not trust an examiner who will not put his/her opinions in writing. If you hire a GPN examiner, you are entitled to a written report of your exam at no additional charge. This report should include the purpose of the exam, the relevant questions asked, the answers given, and the examiners opinion regarding the subjects truthfulness when giving those answers.
Voice Stress vs Polygraph
Polygraph is considered the most accurate method of lie detection today. One of the reasons for this is that the polygraph records various different aspects of a persons physiology, not just one. Different people show reactions in different ways. To look at only one aspect of physiology is to remove a great deal of information the examiner could have used. Voice Stress Analysis (VSA) only measures one aspect of physiology. Even if we accept that VSA can detect stress, that is not an indicator of deception. If a polygraph examiner suggests or encourages the use of Voice Stress technology, that examiners training and qualifications may be questionable. No GPN examiners are currently using or supporting the use of VSA technology.