To me - and this is completely anecdotal - is that there usually seems to be 3 criteria that strangers look for before they open up. They are somewhat overlapp

To me - and this is completely anecdotal - is that there usually seems to be 3 criteria that strangers look for before they open up. They are somewhat overlapping, at least in the way that you can use these them to your advantage: Empathy; being impressionable; appearing weak/ignorant in one or more aspects relating to the topic. So, you don't ask what they did or why they did it. You ask about topics that they may have led them to doing something that they did. Better still, don't ask. Lead the conversation in a way that will make the question will seem more natural. Then you respond with something like: "Wow! How on Earth did you handle that? (Impressionable) If that were me (Empathy) I would have [something outlandish]!!! (Weakness/Ignorance)". So now you seem relateable, and somewhat flawed, even moreso than they themselves. Often, they will try to "teach" you about why your reaction is bad, and what a better reaction would be - often with a "real life" scenario as an example. "Aaah! That's pretty smart! (Impressionable) But I'm not sure I'd be able to handle it as well as that (Weakness)" From here they feel they are in a position of power. Especially if you seem more impressed by some more arbitrary aspect, than concerned about the more obvious implications (Weakness/Ignorance). They often open up more about other things they've done, which may or not be related to the original question. But you're still gaining their trust. Eventually you subtly stopped being impressed by what they are saying. And this is just by body language, not words. Your eyes don't light up when they are "expected" to (Impressionable). You don't smile wryly before they end their sentences as if to say you know you know where it's heading (Empathy). The other person starts thinking: "Why is he/she impressed any more? Is it because they're really that ignorant? Or maybe what I'm saying isn't really that impressive to them? Perhaps I should fill in more details, and maybe I'll tell about some other thing I did" Now I'm not saying this will work interviewing terrorists/criminals. But this has been my own experience for as long as I can remember. People tend to tell me their darkest secrets (even without me asking) within about 30 minutes of meeting me for the first time, especially when alcohol is involved. I rarely ask directly. People just end up telling me things.