Polygraphs should nevern be used. An administrator can interpret the results any way they see fit. It's a perfect avenue for bigotry and other unfair hiring practices. It has no place in society.
Its not about the results and that lets the person running the test interpret things anyway they want. We have seen time, and time again that this leads to all sorts of discrimination that is both against our society's morals and not actually useful as filtering people as well the person doing the discriminating thinks.