Comment by api

The fact that these are still used is a bit of a scandal. They are total bullshit. If they “work” at all it’s by convincing gullible people they work, so they might make someone slip up or confess thinking the magic machine will get them.

Of course things have improved. Decades ago they were trusted a lot more to the point that a lot of innocent people got prosecuted and guilty people went free based on polygraphs. These days they’re inadmissible in court, but they’re still used in the court of public opinion and in some jobs.