but they're admissible as evidence are they not?
Fuck, no. Where did you get that idea?

Everyone knows it's possible to pass a polygraph while lying your face off. It's a matter of heart-rate, eyes, etc. training.
As it is, I would
not be surprised if Trump 2020 happens. Never underestimate the power of the non-information voters in America. All Trump needs to do is engineer (

) a terrorist attack and then invade another "shit hole" (his terms, not mine) country under "patriotism/AMERICA FUCK YEAH!!!!" like Bush did under false-pretenses despite the UN going "uh, excuse me, there's no nukes there. WTF are you doing?" to get the non-information voters riled up despite strong negative opinion about him currently.