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Comment by khawkins | Hacker News Reader

There's a lot of hyperbolic claims being made in the article and these comments which seem unsupported by science. The answer to the question, "can polygraphs be utilized to draw out truth?", is a resounding yes:

>Notwithstanding the limitations of the quality of the empirical research and the limited ability to generalize to real-world settings, we conclude that in populations of examinees such as those represented in the polygraph research literature, untrained in countermeasures, specific-incident polygraph tests can discriminate lying from truth telling at rates well above chance, though well below perfection.

https://www.nap.edu/read/10420/chapter/2#4

Although it is not a silver bullet, it certainly has its applications, especially if the person being interviewed believes it works. Thus, the polygraph test makes sense in questioning sex offenders, for example:

https://onlinelibrary.wiley.com/doi/abs/10.1348/135532508X29...

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> Although it is not a silver bullet, it certainly has its applications, especially if the person being interviewed believes it works.

The whole premise of a lie-detector test is that they are marketed to end user and the public at large as being both accurate and "scientific." That they yield results better than chance isn't particularly relevant: they are not what the sellers and users of them claim they are. The conclusions drawn from the readings of the machines are only loosely based on anything scientific and depend heavily on the interviewer's own personal biases. Yet they determine the fate of people's lives all the time.

Most science isn't accurate, that's why it's filled with p-values. They're often only reporting the mere hint of an effect which allows them to distinguish between a control and experimental population.

Polygraphs are almost certainly not reliable enough to convict someone on, but it's not admissible in court. That doesn't mean it can't be used to help coerce a confession or help lead an investigation. And the fact that you won't face up to the extraordinary amount of evidence showing that it can be useful suggests stubborn ignorance on your behalf.

> The answer to the question, "can polygraphs be utilized to draw out truth?", is a resounding yes

So can tarot cards, and magic 8 balls. polygraphs are bullshit pseudoscience and 100% interchangeable with any other fake bullshit when combined with a experienced examiner and an ignorant/gullible interviewee

...but isn't the answer to the question, "Can the polygraph be used to coerce false confessions from innocent people?" also quite a resounding, "yes"[0]?

Glossing over or attempting to detract from the grossly negative consequences doesn't automatically arrive at the conclusion that it's resultantly a "good" thing.

[0] - https://www.innocenceproject.org/polygraph-tests-contribute-...

What is the use case for a test that can indicate that something is probably the truth or probably a lie when focused on specific incidents? _(According to the study, the reliability drops when used for screening)_

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