How reliable are lie detector tests? What does science say? What is public opinion of polygraphs?

Answer 1

Don't like them or trust them. As a police detective, I will not use them unless ordered to do so by a superior. My experience is that they are unreliable. If a suspect fails a polygragh, you can't use it to prosecute. But if he passes it, a defense attorney can use it to create reasonable doubt; even if there is a mountain of other evidence against him. They can certainly be fooled or show deception when the subject is being totally truthful, that has been proven.

Answer 2

The public opinion of a polygraph is that they are always right in detecting lies.

However, there have been tests that show that lie detectors can get it wrong. The machine can give false positive and false negative readings.

Luckily, today lie detectors are not allowed as evidence in court.

Here is a link that has an article about it along with further sites about polygraphs.

http://www.damninteresting.com/?p=222

Answer 3

Scientifically & statistically, they are very accurate. Information from APA website (link below): "While the polygraph technique is not infallible, research clearly indicates that when administered by a competent examiner, the polygraph test is the most accurate means available to determine truth and deception. Since 1980, a compendium of research studies -- encompassing 80 research projects, involving 6,380 polygraph examinations, and 12 studies of the validity of field examinations following 2,174 field examinations -- indicate an average accuracy rate of 98%."

Public perception, on the other hand, is the reason they are not allowed in court. Since the data is subject to interpretation by a professional, people believe the room for error it too great to allow it as admissible evidence in court.

Things have improved since cops hooked a "bad guy" up to a xerox machine and whenever they thought he was lying pushed "copy" which produced a paper saying: "He's lying!" (true story)

--Z--

Answer 4

truly, sure. there is completely little or no settlement as to how sturdy those exams are, and how fairly the outcomes will be manipulated by try matters. the bottom estimate is a few thing like sixty one% reliability, which will sound truly reliable notwithstanding it really is completely in effortless words 11% extra precise than tossing a coin to make certain if a persons'' mendacity or no longer. If i became to be uncharitable, i'd say the entire charade is a load of pseudo-medical nonsense derived from 19th century quackery. obviously, that nicely conventional scientist and champion of accuracy, Jeremy Kyle, makes use of lie detectors for all time in his shows.

Answer 5

The problem with lie detector tests is that they only respond to changed in your vital signs. But a number of different factors can make them change. Sure, lying can, but so does anxiety and fear. This is the problem with the test, it is unable to determine the cause of the changes. And that's also why they aren't used in court.

Answer 6

They are very accurate, and the lie detector conductor can usually tell when you are employing techniques to "fool" the test.

Answer 7

The public believes they work great. The truth of it is that they can be wrong or at least confused all the time.

They are not considered reliable at all, and can not be used at all in criminal trials for that reason.

Answer 8

they are not very reliable, they are not even accecpted in a court of law, they can be easily beat even if it is a voice type.

Answer 9

They are not 100%, and cannot be used in "court" against you,,

Answer 10

I lied on one and passed.