The US government did extensive research on a potential truth serum. The single most effective solution they found was vodka. Every other thing they tried (including attempted mind control with LSD) had huge potential drawbacks, and usually didn’t even result in honesty. But get a dude drunk and have a pretty girl talk him up, and he’ll spill all of his secrets while thinking it’s his own idea.

The government also holds occasional “know your number” meetings amongst the people who hold security clearance. Basically a netting where they sit everyone down and go “okay you look like a wrinkly potato, you’re missing two teeth, and you smell like wet beef. At best, you’re like a 3 out of 10. Maybe a 4.5 if you bothered to shower before you hit the bar. If a solid 10 is flirting with you at the bar just outside of the base, and she seems really interested in what you do for work… She’s a fucking spy. Know your number, and know what you can reasonably pull. Because if you’re pulling above that number, you’re being honeypotted.”

In vino veritas.