Critics of the polygraph assert that the machine does not detect lies and they are absolutely right! The lie detector test measures physiological responses for deception. Unqualified polygraph examiners are not trained to analyse such responses accurately.
The test is only as good as the polygraph examiner’s qualifications and experience. In addition to calculating meticulously structured questions and the pre-test interview with a subject, in depth analysis of responses is paramount. Unqualified polygraph examiners may, and often do, get it wrong and this is what gives the lie detector industry a bad reputation.
How does a polygraph instrument work?
Most people will have seen a lie detector test in films. The focus is usually on the chart the machine creates where lines are printed. These jagged lines are produced from sensors attached to the body and represent changes in respiration, blood pressure, perspiration and heart rate (pulse). When changes occur, a professional lie detector examiner is able to evaluate the results and determine dishonesty.
More modern technology that is used today collects data using electronic recording systems rather than the moving pen analogue system featured in movies.
Phases of a lie detector test
Lie detector tests can take many hours to conduct due to the different phases that need to be progressed as outlined below:
- Pre-test – this is the first phase when the examiner sits with the subject to explain how the test will be conducted. Any queries the subject may have about the test are answered and questions that will be asked during the examination, reviewed. It is important that the subject has a clear understanding of these questions before the test begins.
- Data – the second phase is when the examiner asks the questions that have been prepared and collects the data from the subject’s physiological responses.
- Analysis – the last phase comprises analysis of the data that has been collected. Having studied this data, the examiner will calculate whether deception was present or not.
What to look for when ordering a lie detector test
Lie detector tests are used in recruitment screening and law enforcement as well as by private individuals. You will want the most accurate results and the only way you can guarantee this is by checking out the credentials of your examiner.
Make sure that the examiner is APA (American Polygraph Association) accredited. They are the best in the world. Use a company that has the latest in lie detector technology and is discreet. Confidentiality is a must when dealing with deceit.
Beware of unqualified polygraph examiners
For a lie detector test to be effective it is imperative that the examiner is qualified and accredited. You wouldn’t let an untrained mechanic fix the brakes on your car and hiring unqualified polygraph examiners falls into the same category.