Most innocent people doubt their innocence when strongly accused even when they know they are right. Just a tiny bit, but in the right setting and with enough wearing you down, you can make innocent people believe they did it. I've seen it happen right in front of me.

That's why you don't talk to cops. Have a lawyer present and use the courts that us taxpayers pay for.

Also why narcissistic and psychopathic manipulators are so dangerous.

They don’t have to be cops. Most aren’t.

I wonder if this is related to people adding ambiguity to what they're saying.

Eg instead of saying "it's 20 degrees outside" they will say "last I checked it was about 20 degrees".

They change their phrasing because they want others to not think that they are wrong. By doing this they undermine their own credibility though.

Hmmm. People who make absolute statements like that generally* undermine their own credibility in my mind.

*I do it lots. Partly because the way my mind runs, I can nearly always (lol, can't help it) come up with possible conditions where I'd be wrong.

I am the opposite. I constantly add ambiguity even when I'm sure. I'm trying to learn to do less of it.

But what's the point of making innocent confess to false crimes in this setting? (i.e. requiring polygraph for job application)

I would imagine the entire point of doing a test would be to find out who is innocent and who is lying about being innocent. If you pressure the innocent into false confession, wouldn't it just make everything even more difficult?

In the context of a job application? Making up excuses to hide discrimination, maybe artificially limit the pool of applications to get around other hiring restrictions? Put the applicant on the back foot or make them share information they normally wouldn't? There are probably many ways to abuse it.

Good points. It never occurred to me that there are situations where recruiters intentionally try to remove legit applicants from the pool.

The polygraph would be used as the “bad cop” in the good cop, bad cop routine. After a line of questioning where the interrogator/polygrapher suspects lying, or is fishing for more information, they might say something like “everything sounded good but the machine is showing some deception. Is there anything you can think of that might be causing these readings? Anything you didn’t tell me? I want to get you out of here, but we need to resolve these results.” If the machine does show spikes during certain lines of questioning but not others, for instance about someone’s timeline on the day of a murder vs their relationship to the victim, it can be a reason to pursue further questioning in that area.

Given all the ways polygraphs can be misused or abused, the only real use I see is as in interrogation tool. But given the issues with false confessions in general, I think the interrogation should hold less weight, but that is a whole other issue.