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What Are Polygraph Tests?

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What Are Polygraph Tests?

Polygraph tests are a type of test conducted using various electrical signals and readings to try and determine whether a person is lying or not. These were often used in the past in many police and criminal investigations, especially when dealing with witnesses or suspects in the crime. Polygraph tests are more commonly known as "lie detector tests".

They are common in a criminal context but can also appear in other areas such as employment purposes. In a criminal investigation, no person is ever required to submit to a polygraph test against their will.

Are Polygraphs Admissible in Court?

The admissibility of polygraph tests in court will depend on the rules and laws of each particular jurisdiction. In some states (AZ, CA, GA, NV, and FL for example), polygraph evidence is admissible in a criminal court, but only if all the parties involved agree to their use.

In many states, polygraph tests and evidence is deemed to be completely inadmissible, even if both parties consent to their use. These types of states include IL, NY, TX, PA, and the District of Columbia.

Lastly, other states may have a mix of rules regarding their admissibility and use in court. For instance, Georgia is an example of a state that allows a person to sue a polygraph conductor if a false result on the test caused them damages. Details like these will vary by state.

Why Are Polygraphs not Admissible in Court?

The main reason why polygraphs are not admissible in court is because many agree that they can sometimes be very inaccurate. There are many factors that can lead to an inaccurate lie detector test, including:

  • Deficiencies or defects with the machine and equipment
  • Bias in the polygraph conductor or other parties involved
  • Inconsistent responses on the part of the person being interrogated

Another aspect is that a person who is undergoing a lie detector test will always be under a certain degree of stress. This stress can interfere with the readings and can also affect the way that the person responds to questions.

In court, there may be other ways to determine a person’s character and reliability when testifying. These may be relied upon in lieu of conducting a polygraph test or using such test results.

Do I Need a Lawyer for Help with Polygraph Test Issues?

The laws regarding polygraph tests can often be difficult to understand. They are different in each region and may also contain several clauses and provisions that require careful attention in order to understand correctly. You may wish to hire a qualified criminal lawyer in your area if you have any questions or if you need legal representation for a court case. Your lawyer can help inform you of your options and your legal rights as a defendant.

Photo of page author Jose Rivera

, LegalMatch Legal Writer

Last Modified: 01-17-2014 02:16 PM PST

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