They're mostly discredited here as well. Criminal defendants can't be forced to take them. In virtually all states, defendants can suppress polygraph evidence. In some of the states where polygraph evidence is allowed (by consent of defendants), the defendants apparently also get a civil cause of action against the polygraph vendor.
Unfortunately, we still use them as part of a hazing ritual to get clearance for national defense projects. But the poster upthread is probably right that those kinds of projects aren't the ones you want to be working on anyways.
The interesting thing about polygraphs is that they can be an effective interrogation tool as long as the subject believes they work. (but then again so Santa Claus if the subject believes in him)
For instance the interrogator says, "the polygraph says you're hiding something from me, are you sure there isn't something you want to get off your chest."
The should however, be banned completely because the false positives are so high that we are crippling many of the agencies that rely on them. We're forcing them to drastically reduce their potential talent pool based on pseudo science.
> the false positives are so high that we are crippling many of the agencies that rely on them.
Even worse than that, it selects for people who lie with impunity without any visible or emotionals qualms about it -- basically it selects for psychopaths.
It does have an effect on subjects who believe it works, it's causes them to believe that the interview knows they are lying. I would expect this to select for good liars among people who believe the lie detector works.
Unfortunately, we still use them as part of a hazing ritual to get clearance for national defense projects. But the poster upthread is probably right that those kinds of projects aren't the ones you want to be working on anyways.