Lie Detector Test Options

Differences Between Polygraph and Voice Stress Tests

Two Formats Of Lie Detection To Choose From

The polygraph and voice stress have much in common, but also have some significant differences.

Polygraph Test Voice Stress Test
98% Accurate 98% Accurate
FREE Written Report FREE Written Report
NO Certificate FREE Certificate
Takes 2-3 hours Takes 15-20 minutes
Has countermeasures to alter results NO countermeasures
Attachments required on body NO attachments required
Results affected by drug/alcohol use Not affected by drug/alcohol use
Test done in person due to attachments Test done over the phone or in person
Can have inconclusive results NO inconclusive results
Measures heart rate, blood pressure and other changes in the body Measures involuntary reflex in the voice called a microtremor
Used by some Police and Sheriff departments, attorneys and business owners Used by some Police and Sheriff departments, the CIA, FBI, NSA, Homeland Security, U.S. Military, etc.

Since most people in the private sector have heard of the polygraph test, there really isn't a need to discuss this in great detail. However, since the voice stress analysis (also known as voice polygraph) is new to most people, we will take the time to explain it here and tell you how the CIA, NSA, FBI, Homeland Security, Police and Sheriff departments, attorneys, business owners and many others use the voice stress to do their very important jobs.

The voice stress lie detector test was developed by the U.S. Military over 50 years ago for covert operations, as a means to determine deception and gather intelligence, as well as a way to replace the traditional polygraph due to some of its flaws. This technology allowed them, as us today, to analyze ANY type of voice recording, including telephone conversations, television and radio programs or audio from cassette tapes, CDs or DVDs, as well as from MP3 or WAV files.

You may be asking yourself, "How can you determine if someone is being deceptive or not just from a voice recording?". Well, that's a great question...read on for the answer.

The voice polygraph (voice stress analysis) test measures an involuntary reflex in the body that occurs under stress called a microtremor. This microtremor occurs at a sub-audible level, which means it's below what the human ear can hear. The microtemor is usually between 8 Hz to 12 Hz and the human ear can hear from about 20 Hz on up. This is why we have to record then entire testing process so that we can use our computerized instrumentation to analyze these changes for deception.


Insurance Industry Uses Voice Stress Testing

The Insurance industry is probably the biggest commercial user of the voice polygraph (voice stress analysis) test technology. For example, when someone has an auto accident, they will need to explain to the insurance company what occurred. As they are telling their story over the phone, the entire conversation is being recorded and will then be later analyzed for deception. If the insurance company finds that you were lying about your story, then they won't pay the claim.



Police 911 Calls Are Analyzed Using Voice Stress Analysis

This technology has been used for many years to monitor suspicious 9-1-1 emergency phone calls. Whenever an operator feels that the person on the other end of the phone is acting out of character for someone undergoing an emergency, the tape recorded conversation is analyzed to determine whether or not additional investigation is necessary.



Homeland Security Relies On Voice Stress Testing

And, Homeland Security relies on the voice polygraph (voice stress analysis) technology to help protect our country from terrorist activities. They will tape record and analyze the terrorists phone conversations. The voice polygraph must be a viable solution if the U.S. Department of Homeland Security is using it to protect us.



FBI & CIA Use Voice Stress Analysis Testing

The CIA and FBI use if for gathering intelligence among other purposes. In any situation where they can record and analyze the voice, they rely on the voice polygraph.



Police & Sheriff Departments Utilize Voice Stress

Many Police and Sheriff department use it for their investigations, as well as use it for their pre-employment screening of prospective policeman and law enforcement officers. Telephone wire taps from phone conversations can analyzed for deception.



MLB Owners Test Players Using Voice Stress

Even some professional baseball teams make their players go through the voice stress testing process over the phone each month for behavioral purposes. With more and more professional athletes in the news, team owners, managers and coaches want to be sure that their players are acting in a professional manner and in accordance with their contracts.


Post-convicted sex offenders have to go through this process over the phone each month as a part of their probation to make sure they're following the guidelines. They are asked questions like "Have they been within 1 mile of a public park or elementary school?"

Now, many airports are starting to use this technology to screen travelers.

Additionally, the voice polygraph (voice stress analysis) test is used in criminal and civil cases. Many courts throughout the country allow these test results to be admissable. Be sure you check with your attorney to confirm if the court that is handling your case allows these tests as admissable forms of evidence.

You may be asking yourself, "Can this really work for my situation?" The answer is "Absolutely!" If it is used and relied upon by the CIA, FBI, NSA, Homeland Security, the military, the Insurance industry and numerous other law enforcement and government agencies, as well as used in criminal and civil cases, then it's definitely good enough for your situation. Don't let the fact that it's new to you stop you from using this widely used and heavily relied upon technology.

The only limitation to this technology is if the person taking the test uses Skype or Vonage. These services cut off the low and high frequencies, which include the frequency we measure. Otherwise, any traditional phone line or cell phone with good connectivity will work.

"Things went exceptionally well. The gentleman who performed the test was very through in explaining everything and making sure that any and all questions that I had asked were explained and very well understood. If services are ever needed again I will definitely not hesitate to use Nationwide Polygraphs again. Could not be more happy with the help we were given with the process."
- Jenna B.