The “lie detector” (wide circulation term), in fact, refers to the polygraph device for recording psychophysiological reactions, namely: breathing, blood pressure, pulse, and electrodermal reaction, characteristics of emotional tension.
The polygraph does not record the lie as such, but the physiological changes of the body during the various emotional states that accompany the simulation. The consciousness of guilt, mobilizing an emotional state that can be masked with difficulty, causes the subject to react emotionally, whenever an object is presented to him or a question is asked about the crime committed. A conscious lie, in addition to the mental effort it requires, also produces a certain state of emotional tension.
However, if the person being tested shows anxiety for other reasons or, on the contrary, has the ability to control their emotions very well, the results become misleading and irrelevant. These conclusions led to skepticism around the accuracy and relevance of the supplied data from the beginning of the use of the device (the origins of the modern polygraph date from 1913).
The American Polygraph Association (APA) notes that a properly conducted test with specific questions (as opposed to using questions with multiple or complicated answers), will give a 95% to 98% accuracy.
How Much Does Lie Detector Testing Cost?
The cost of a lie detector test is greatly influenced by the amount of time spent in order to take this test, with the ones taking the whole day being the most expensive. The average price of a test conducted by a certified professional is anywhere between $250 and $2,100. The cost of a typical test that takes two hours and checks only one issue is anywhere between $220 and $850. For instance, Holland Polygraph Services, located in Washington state, charges around $430 for a test, but the costs can increase rapidly.
The tests performed at The Polygraph Examiner, which has offices in Georgia, South Carolina, and North Carolina, cost $370 to $650.
If you choose to take such a test at the Capitol Polygraph, located in Michigan, be prepared to pay anywhere between $350 and $550.
You have the possibility to take this test from the comfort of your home. A home lie detector costs $100 to $730, but you should know that the accuracy of these tests is not considered reliable. For example, De-FIB-ulator voice-stress test costs around $100. Also, you can find older models of lie detector units that can be bought for almost $720 on eBay.
Lie Detector Testing details
There are 3 distinct phases of polygraph examination:
- Pre-Test Discussion: The polygraph examiner will explain your legal rights and the voluntary nature of the exam. A background information analysis will then follow to assess your eligibility for the examination. The examiner will help you formulate the questions and will explain how the polygraph tool works (approximate duration: 40 minutes).
- Testing: the examiner will inform you of all the questions of the test, will explain the operation of the device, and will have you sign a Declaration of Consent to the Examination (by which the subject gives his written consent to be subjected to this test). Then, several polygraph tests (maximum 3) will be performed by administering the agreed-upon questionnaire (approximate duration: 30 minutes).
- Discussion and Post-Test Analysis: the examiner will analyze the polygraph diagrams and will make a report, which will be handed to the client (approximate duration: 40 minutes).
Important things to consider
At an international level, so far, no scientific study has been published to make the polygraph a scientific tool, which is why it is not considered a means of proof in court.
The German Federal Court of Justice, for example, considers polygraph-based evidence to be inherently unconvincing and unacceptable in court, and in the United States, the lie detector test was subjected to a test called “Frye” in order to be recognized as evidence in court but failed to pass it.
The American Association of Police Polygraphists is on a mission to increase the safety and security of local law enforcement officers. They offer an online database that has listings for lie detector testing professionals across America, searchable by location or type/license status, all with contact info so you can reach out right away if needed.
Polygraph tests are admissible in court, contrary to the popular myth. The Polygraph Examiner provides an outline of previous cases involving polygraphs and their successful use as evidence.
Polygraphists are the most qualified professionals in lie detection. They have to be certified, undergo training programs that last 6 months or more and pass tests that are recognized by the American Polygraph Association.
The results of using the methods of detecting the simulated behavior are not affected by the passing of time so that no matter how much time has passed since the activities investigated occured, the subject will have reactions as strong as on the first day.
Does it hurt? No. You may feel slight discomfort due to the sleeve (for blood pressure) on your arm, which is swollen throughout the test but is not more uncomfortable than if a nurse or doctor would take your blood pressure. In fact, the sleeve will be less swollen than in a medical situation, so the discomfort should be minimal or not at all.
How can I save money?
If you are going to take more than one test, you may be able to get some discounts from the professional testing services. For instance, C&C Polygraph, which has a number of offices in Idaho, offers different discounts for multiple tests. Also, they offer a 20% discount to customers that return for more tests.
Another example is the Equalizer Polygraph, with offices in western Washington, that offers a $55 discount from the total costs for the „His and Her” tests, taken by both partners for infidelity.