Should I Take a Lie Detector Test at Work?

When your boss asks you to take a lie detector test, do you have to do it? Should you do it? Read on to learn your rights and one lawyer's advice.

(Image credit: Rich Vintage Photography (Rich Vintage Photography (Photographer) - [None])

“Mr. Beaver, I am in upper management at a high-quality meat processing plant in the Midwest. Over the past several months we have experienced a significant loss of expensive sides of beef, but it has not been continuous, just time to time.

“I have an idea who is behind this theft. I believe it is a group of employees, but can’t say for sure. It is more than a feeling, more than a hunch, but I do not have real evidence of who is doing what,” “Jody” wrote.

“Our CEO wants to run all employees on a polygraph to be administered by a private investigator. Am I legally obligated to submit to the examination? What happens if I refuse? Can I be terminated? What has been your experience in your law practice with the polygraph? Do you believe that it accurately can detect who is telling the truth? Are some people more likely than others to fail the test?”

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Some Facts about Polygraph Examinations

The first polygraph dates from 1920 (opens in new tab), when a California-based policeman and physiologist, John A. Larson, developed an instrument to measure continuous changes in blood pressure, heart rate and respiration rate in order to aid in the detection of deception. The operative theory was that your body’s own reactions would reveal lying.

Until 1988, lie detectors were routinely used on employees and job applicants, and they still are for certain types of employment. Employers often asked employees and applicants questions about private matters — often having nothing to do with the actual job — and the lie detector would reach a conclusion as to their honesty. Even people who were truthful often appeared, to the machine, as deceptive.

Eventually the accuracy of polygraph tests came to be seriously doubted. The Federal Employee Polygraph Protection Act (opens in new tab), passed in 1988, virtually outlawed using lie detectors in connection with employment. Under the act, it is illegal for private companies to:

  • Require, request, suggest or cause any employee or job applicant to submit to a lie detector test;
  • Use, accept, refer to or inquire about the results of any lie detector test conducted on an employee or job applicant, or;
  • Dismiss, discipline, discriminate against or even threaten to take action against any employee or job applicant who refuses to take a lie detector test.

The law also prohibits employers from discriminating against or firing those who claim its protections. Government employees are generally not protected by this law, however civil service rules offer some protection.

When Lie Detector Tests May Be Used

The Employee Polygraph Protection Act permits polygraph tests with jobs in security and handling drugs or in investigating theft or other crimes committed by employees. Before an employee can be required to take the test, a 48-hour notice must be provided, which states that you are a suspect. A provable, reasonable suspicion that you were involved in the theft or other conduct triggering the investigation must be established.

It is important to note that an employee may refuse to take the test. Additionally, the act’s protections do not apply to employees of federal, state or local government, nor to certain jobs that handle sensitive work relating to national defense.

State laws often further restrict the ability of running an employee on the polygraph, so that is something important to look into.

Controversial at Best

Some years ago, the American Psychological Association (opens in new tab) issued this statement:

“The accuracy (i.e., validity) of polygraph testing has long been controversial. An underlying problem is theoretical: There is no evidence that any pattern of physiological reactions is unique to deception. An honest person may be nervous when answering truthfully and a dishonest person may be non-anxious. Also, there are few good studies that validate the ability of polygraph procedures to detect deception.”

Our Own Experience

Years ago, I taught part-time at California State University in Bakersfield and invited the D.A. Office’s polygrapher to demonstrate how the machine worked to the class. One member was selected. He was an “Army Brat,” having lived in several countries, and spoke Spanish, French and German. We heard him speak those languages.

Hooked up to the machine, he was asked if he spoke those languages, and replied affirmatively. The machine said “Deceptive!” On it went, he gave honest answers, yet the machine called him a liar.

“So, how do you explain this?” I asked the polygrapher.

“Some cultures (or families) where guilt is a strong influence in the raising of children can dramatically influence how someone will do on a polygraph, and I’ve seen this before,” he commented.

With that experience in mind, my advice to Jody would be to politely decline being tested on the polygraph. While innocent, that scent of suspicion could do him great harm.

This article was written by and presents the views of our contributing adviser, not the Kiplinger editorial staff. You can check adviser records with the SEC or with FINRA.

H. Dennis Beaver, Esq.
Attorney at Law, Author of "You and the Law"

After attending Loyola University School of Law, H. Dennis Beaver joined California's Kern County District Attorney's Office, where he established a Consumer Fraud section. He is in the general practice of law and writes a syndicated newspaper column, "You and the Law (opens in new tab)." Through his column he offers readers in need of down-to-earth advice his help free of charge. "I know it sounds corny, but I just love to be able to use my education and experience to help, simply to help. When a reader contacts me, it is a gift."