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Who Should Use a Polygraph?

  • April 19, 2007
  • by PInow Staff

A polygraph can be a useful tool that can be used as part of a larger investigation to get answers. However, businesses interested in using the test need to follow the law to the letter to avoid legal action.

Polygraph tests have caused a lot of controversies and have generated many myths over the years. In November 2006, A Jacksonville, Florida firefighter fought the results of a polygraph test that he says was inaccurate. The man took the test as part of an internal investigation into an incident which allegedly involved nooses being placed on his uniform. The polygraph results suggested deception, but the firefighter has always consistently claimed that he found nooses on his uniform an act that can be seen as a hate crime or a form of harassment. Administrators of the test are defending the polygraph as a reliable tool but the firefighter and his attorney are pointing out the many documented studies that suggest the test is highly fallible.

A polygraph is sometimes called the lie detector test but this is a misnomer. The test is really nothing more than a way of measuring the body's responses when questions are asked. Polygraph examiners compare physical responses to questions to see how a subject reacts to questions for which the answer is known (such as what is your name?) and to questions for which the answer is unclear (such as where were you on the night of September 30?). By comparing the two, proponents of the polygraph claim that deception can easily be uncovered, since people react physically when they lie.

Should you look to a polygraph to get answers?

There are many situations when someone may want to use a polygraph test:

  • Defendants interested in proving their innocence. Defendants involved in a case do not always have hard evidence to prove their innocence. In some of these cases, voluntarily taking a polygraph test can impress on the court that the defendant has nothing to hide and is telling the truth.

  • Attorneys involved in criminal trials or civil cases -- and their plaintiffs. Attorneys do not always like to use polygraph tests since the test results are not predictable. Nevertheless, polygraph test results can be used as part of the larger evidence of a case to prove guilt or innocence. Also, polygraph examiners can be called to the stand to testify.

  • Banks and other businesses involved in internal investigations. Corporations running internal investigations into theft, crimes, or other workplace dangers will sometimes use a polygraph to determine whether employees are being truthful in an investigation and whether employees are loyal to a company.

  • Some hiring committees. Some government agencies and companies use polygraph testing when hiring candidates. This type of screening is most common in jobs that require a high-level security clearance or considerable responsibilities.

Legal issues to keep in mind

According to the Employee Polygraph Protection Act of 1988 ("EPPA"), not everyone can use the polygraph test. According to the act, employers can only ask their employees to take a polygraph test as part of an "ongoing investigation" into a case that involves business losses or financial losses to the company. The employer can only request the test of employees who are reasonably under suspicion for the crime or incident in question. Employers cannot randomly use the test to uncover theft or crime in the workplace and employees always have the right to refuse to take the test. Even in cases where a polygraph test seems to indicate wrongdoing, the test itself cannot be used to indict an employee. At most, the test can be used as part of an overall investigation or as supporting evidence.

What do businesses need to know?

Businesses interested in using the polygraph as part of company investigations need to proceed with caution. Laws protect employees and potential employees and overstepping these laws can mean long legal battles. Savvy businesses know that hiring a professional investigator to run polygraph tests or internal investigations is often smartest. A good, local investigator can run a thorough, legal check which provides real answers that can stand up in court. Now, finding such an investigator is easier than ever, thanks to the Worldwide Directory of Private Investigators. The Worldwide Directory of Private Investigators is a free polygraph resource, with lots of useful information. It is also a database that allows anyone to find experienced, local investigators.

About ( is a Worldwide Directory of Private Investigators that enables law firms, corporations, and the general public to find investigators anywhere. strives to be the most trusted resource on the web to locate qualified investigators. All investigators listed on are pre-screened and must meet specific listing requirements. was developed by the team that brought you the Process Servers Directory (

Visit to find investigators who can help with all your investigation needs.

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