I mean, unironically, this is what polygraphs exist to accomplish. They aren't reliable instruments and a lot of the "results" boil down to a technician trying to figure out if your heart rate increase or sweaty palms are a result of you lying or the AC in the room not running properly.

By the time someone's decided to strap you into a ploygraph machine, you're already "guilty" in their eyes. They're just looking for an excuse to slam the book on you.

But if anyone knows that already, it’s FBI staff.