You and GP really need to read the article fully. Even without doing other research, you dismiss the concept based on a false premise that the article itself clarifies..
"they know these kinds of tests can be unreliable, being confronted with the chance to take one can filter out disingenuous defendants."
So if I was charged with a crime and when offered a polygraph test and I refused it on the grounds that it is unreliable I would be treated as being likely to be "disingenuous" and therefore presumably more likely to be guilty?
Edit: I meant more likely to be thought of as guilty.
In other words it's the modern equivalent of the ancient practice of trial by fire.
Except that in this case the defendant should have a defense attorney who will tell them the truth, that the ordeal itself is a farce and the real test is whether agreeing to suffer it will convince the prosecutor.
Which destroys its value as a filter and converts it back into its true form, a waste of tax dollars on pseudoscience BS. (And a method for prosecutors to coerce innocent defendants into giving up their right to remain silent or communicate through their attorney.)
William Casey, who was Reagan's first CIA director, told journalists that passing polygraphs is an easily learned skill. Some may not need the training: if there is no psychological stress involved in lying, why should there be physical symptoms?
Which is still irrelevant here. The willingness - or not - to take the test acts as a filter. Beyond that, a case review is carried out. If the case review finds they have sufficient evidence, the test does not matter. If the case review finds they have insufficient evidence, then you should not have been charged in the first place.