Determining the truth is one of the biggest problems facing jurors, judges, and law enforcement officials. Because of this, witness credibility is crucial throughout a trial.
Read More: Attorney Lie Detector
Even though witnesses are required to swear to speak the truth before testifying, judges and juries frequently receive contradicting evidence that suggests a witness is lying. Thus, if a lie detector test is accurate and admissible as evidence in court, it may be able to assist the jury in ascertaining the truth. As it happens, neither is accurate.
Speak with a skilled criminal defense lawyer for assistance if you are being forced to take a lie detector exam because you are being investigated for possible criminal charges, or if you have already taken the test and are concerned that it will be used against you. Your legal representative can safeguard your rights and provide you with choices for assembling an effective defense.
How Accurate Are Lie Detectors?
In summary, lie detector tests are typically not accepted as acceptable evidence in court and have dubious reliability. When applying for some government job positions, they may be utilized in certain investigations and decision-making processes.
It would appear that the polygraph exam, also called the lie detector test, has the technology to eliminate uncertainty in identifying the truth-tellers and the liars. That was how they appeared in a lot of crime dramas on television. However, the individual giving the test, the equipment being used, and the test subject can all affect how accurate the findings are from a lie detector test.
Therefore, unless both parties consent, polygraph findings are often not admissible in criminal proceedings. Even yet, several jurisdictions forbid the use of polygraph exams as evidence, and a trial judge frequently retains the authority to approve or disapprove a polygraph test.
Opponents of permitting lie detector test results to be used in court contend that juries may accept the findings without taking the test’s accuracy or the possibility of false positives into account. In jurisdictions where the findings of lie detector tests can be used in court, both parties are permitted to provide evidence supporting their positions on the reliability of the test.
Using control questions like “What is your name?” and then more in-depth inquiries that might suggest claimed guilt or innocence, polygraph test findings reveal physiological changes, such as variations in the test-taker’s heart rate.
Which States Permit Polygraph Exams?
The admission of evidence from lie detector tests is a matter that the U.S. Supreme Court leaves to the discretion of the individual states. Certain states forbid the use of lie detector evidence.
States with criminal justice systems that permit the use of polygraph test findings as evidence in court include:
Alabama
Arizona*
Arkansas
California*
Delaware
Florida*
Georgia*
Idaho
Indiana
Iowa
Kansas
*Nevada
New Jersey
New Mexico
North Dakota
Ohio
Utah
Washington
The Wyoming
States marked with an asterisk (*) permit the use of lie detector evidence in specific situations or only in situations when both parties consent to its use. You may be able to present expert testimony on the inaccuracy of the test findings in states where it is permitted.
The Case for the Admissibility of Lie Detectors
Advocates of using polygraph evidence in court argue that the tests are often dependable and provide valuable information. One defense of the device is its ability to detect minute variations in skin conductivity. Many experts, however, disagree with this supposition. Because of this, the Supreme Court stated that there is no trustworthy scientific data about the accuracy of lie detector tests, leaving the decision up to individual states.
The Operation of a Lie Detector Test
In essence, the subject is asked a series of questions while the polygraph machine is strapped to their body. In order to ascertain if a subject is telling the truth, the polygraph test tracks their physiological reactions to the questions, such as an increase in blood pressure.
How may this result in an incorrect outcome? For instance, even if someone is speaking the truth, they might still be anxious and concerned about the test’s outcome, which could raise their blood pressure readings and trick the machine into believing they are lying.
Is It Time to Take a Polygraph Exam?
When interviewing witnesses and suspects, many lawyers and police officers still employ lie detector tests, even though the findings aren’t always acceptable in court. Prior to administering a polygraph test to a suspect, police enforcement must also give you your Miranda rights warning.
If police want to interrogate you about a crime, you should never consent to undergo a lie detector test without first speaking with a criminal defense attorney. Your attorney will assist you in considering the potential implications for your case.
Speak with a Criminal Defense Attorney Right Now
In addition to providing you with legal counsel, a criminal defense attorney will hold prosecutors and law enforcement officials responsible. You can also tell your lawyer anything under the attorney-client privilege. Police may use the test results to strengthen their case even if they cannot use them as evidence against you. You can choose not to take this exam, just as you should always make use of your rights to an attorney and to remain quiet.