If lie detectors are unreliable and not admitted in court, why are they still being used?

The point of using a polygraph in a criminal investigation is not to determine whether or not a person is guilty or innocent. That's partially why the results are inadmissable.

A wise investigator/polygrapher keys in on answers that produce a difference from the suspect's "baseline." They use this to guide their questioning along lines that may produce more information or even an admission of guilt from the suspect.

Children and mentally ill people cannot be valid polygraph subjects since their beliefs/behaviors will not produce significant changes from baseline.

Hope this helps.

Actually they can be used in some courts if the prosecution and defense agree. Also, the judge has to be in agreeance. However, to answer your question I think it is a good starting of point for law enforcement. As most people already know, if you are innocent, then why not go ahead and take the test. I will admit a lot of people will take the test because they think it will make them seem like they are telling the truth, and they may also feel if they don't cooperate, the authorities will unfairly target them. But, there are a lot of reasons and variables involved in such a case, and sometimes it's a matter of aid to the prosecution or the defense.

Just because the results are not admissible doesn't mean polygraphs are useless. Like anything else in police work, it can be one element of the puzzle. As long as the officers understand that there are false-positives and false-negatives and don't base their entire investigation 100% on a polygraph result, the polygraph process can significantly narrow the field of suspects.

Plus, true psychopaths and sociopaths are very rare.

If you were a detective and asked Joe Blow citizen to take a polygraph, wouldn't you also be watching his to see what his reaction is to your request? A typical person who is 100% innocent is more likely to leap at the opportunity to prove this. A person who is guilty might be more reluctant.

I consider it as just another tool in the investigatory tool box. It shouldn't ever be the only evidence, but it has its place!

They are still being used because they are only unreliable and inadmissible when the results may aid the defense. If you submit to a lie detector test, the results are kept within the police department, unless the detective feels that it may help their case. If the defendant thinks that it may help their case, they have to go through the process of discovery in order to even just see the results.

Not feeling guilt isn't what can let you pass a polygraph. And they really aren't that unreliable it is just that they aren't 100% reliable.

The vast majority of people can't fool a polygraph with a good operator.

Because the people who use them don't work for the court.

because they are still an effective screening tool

thats why luck was invented