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March 10, 2015

Remember all those old crime movies that inevitably showed a scene in the police station with someone hooked up to the old lie detector machine? Many of those instruments are actually still in use today. It is the antique-looking analog version of the instrument, usually portable and compact. It incorporated ink that needed filling and routine maintenance, but the basic fundamental and operational aspects of the vintage testers are identical and as accurate to the modern, software-based computerized version of the traditional polygraph. ‘Polygraph’ means many writings. There is a variety of data that is acquired by the sensors and electrodes of the instrument. It records a number of simultaneous physiological activities, involuntary bodily responses in relation to the timing of the questions asked the subject by the examiner. The behavior of the cardiovascular, respiratory and sweat gland body systems are scrutinized both individually and in concert with each other. The software version can be loaded into a laptop with the sensors attached to a USB port; this offers portability, no maintenance, and the addition of a final computer analysis called a Polyscore.

The Polygraph Process

Many are unaware that there are three distinct phases to administering any polygraph test. This is different than typical TV show or movie where we generally join the process during the exact moment of the most pertinent question being asked. In the real world it takes 1½ to 2 continuous hours to complete the full test.

  1. Pre-Test Interview – This is where the person is allowed plenty of time to get acclimated to the room and the examination. There is an exchange of information, background specifics are acquired, and the person is made to feel comfortable. The equipment and process of the test is thoroughly explained, and any concerns addressed. There are no secrets or surprises, and in fact, the person is given all the questions – along with the order they will be asked - completely in advance. Each and every question is reviewed and addressed. The sensors and electrodes are shown and discussed, and the way the equipment works is explained. The subject becomes familiar with the examiner’s voice, mannerisms, and personality. Then there is a ‘rehearsal’ or ‘dry’ run, and this ensures that all the questions are understood, and the process is experienced exactly as it is anticipated to occur during the actual examination phase. The individual will now know without any doubt what to expect on the actual test. This is considered to be the most important phase of the entire test.
  2. Actual Testing Phase – The sensors and electrodes are attached and the test is administered. At least three consecutive identical tests are done, each one lasting approximately five minutes. There are most likely only three relevant questions, and all the others are irrelevant to the actual investigation – like, “Is today Tuesday?” - along with some comparison questions developed during the pre-test interview with the examinee. Responses to these queries are compared to those of the desired questions that are the focus of the examination.
  3. Post Test – The person administering the test completes their analysis and documents their opinion.

The examiner is required to have received proper training and experience, and an organization like the American Polygraph Association can provide this. Some states go the next step and require all examiners to be registered and licensed. The polygraph test is NOT 100% accurate, but in the hands of an experienced and well-trained examiner, it approaches a 95% accuracy level. Occasionally, there are some techniques the subject attempts to incorporate in an effort to skew the results of the testing. These ‘countermeasures’ could result in an inclusive result. There is information readily available across the Internet that explores a variety of ways to alter one’s body responses, using methods like taking sedatives to reduce anxiety, overuse of anti-perspirants, and the incorporation of responses that are repetitive (body movements or certain identical actions after each question) to attempt to cover up or override the body’s more subconscious responses. An experienced examiner, however, is very familiar and wise to such tactics, and so is the software that is evaluating all the aspects of the test in real time and in final analysis.

Can Your Company Give Lie Detector Tests to Employees?

Some companies can be quick to want to administer polygraph tests to employees. The professional advice is to proceed with extreme caution, and have a full knowledge of the legal ramifications, and the alternatives to an exam that may actually be inappropriate in most circumstances to administer. In 1988, the EPPA (Employee Polygraph Protection Act) established polygraph related Federal law for private and commercial businesses. It addresses usage for most companies; businesses under contract with the United States government, and certain investigative and armored cars services, are exempt from its reach. If proper EPPA procedures are not adhered to and diligently followed, there is a risk of a lawsuit being filed by any employee who feels the investigative process compromised the rights that are granted to them by this law. For a private company to give an employee a lie detector test, it is imperative that they are fully cognizant of the law and the ramifications if they do not follow its protocol fully. Here is a brief overview. Technically an employer can administer a polygraph test – but only after a prerequisite of items are diligently accomplished and documented. The employer must first conduct a thorough investigation, and acquire certain pertinent information. If employee theft is suspected, for example, the employer needs to first launch an investigation that will narrow down the range and amount of those suspected. Twenty initial people should be reduced to just a small handful of the most likely suspects. At that point the employer can ask those individuals to take a polygraph examination. If they refuse, they cannot be disciplined, reprimanded, fired, or thought to be guilty of the topic of the investigation. They have to be given a 48-hour leeway window to decide and agree or disagree to take the test. During this period they can talk to an attorney or their union rep. Very few attorneys would probably advise their client to take such a test. If they do agree to the polygraph examination, they then need to sign several documents outlining the test and the reason they were asked to be subjected to it. An additional waiver states clearly that they are doing so of their own free will.

Polygraph Concerns & Limitations

Often by the time advice is attained from a professional security investigative service, a line has already been compromised or crossed. If an employer has even subtly tried to scare or threaten an employee by stating something like, “We can put you on a polygraph if you don’t tell us the truth about…, ” the company may have already exposed themselves to the possibility of a lawsuit. That’s why businesses and their executive management and human resources teams should be well informed as to the legal aspects of all investigation-related communication and implications expressed to their employees. The better and wiser approach is to consult with a professional security service that has expertise in this area. They will have investigators available who can oversee the process and procedures to ensure that everything follows the letter of the law. The penalty is exorbitant, and companies can subject themselves to a $10, 000 per day fine for just inappropriately asking an employee to take a polygraph test. The fine will continue each day until the issues are deemed resolved. Polygraph testing should be limited to the absolute right situation. That is why all are advised to limit the risk of a lawsuit, and first consult a professional agency skilled and knowledgeable in all aspects of polygraph testing, employee screening and investigations, risk assessment, and related legalities. Recommendations can also be made regarding alternative methods to gain the information desired from employee investigations, and if appropriate, this may incorporate background checks and other data collecting means. As an additional safeguard moving forward, your company can receive a comprehensive overview on how to successfully eliminate any identified areas of security weakness that can potentially be exploited by employees.

Employee Screening
Lie Detector Testing