But what happens when you tell them the truth, and they keep on using the blowtorch?
So if you and Bob robbed the liquor store, and the cops start using a blowtorch on you to find out your accomplices, and at first you clam up, then you throw out some fake names, then you give up and name Bob. Except, what does that look like from the interrogator’s point of view. He tortured you and you named Steve. He kept on torturing you and you named Pete. He kept on torturing you and you named Bob. Why does Bob’s name make him stop torturing you? Because you really really mean it this time? How does he distinguish between when you named Bob and when you named Pete?
This is why people who are tortured confess to whatever crime the torturer thinks they are guilty of. He knows you’re guilty, otherwise he wouldn’t be torturing you. So therefore, you’re going to be tortured until you tell him the truth–as he sees it.
Note that torture can work in a situation where the torturer can easily check the truth value of a statement. So if he demands the combination of the safe, and the safe is right there, and he’s going to keep torturing you until the safe is opened, then you’re going to tell him the combination of the safe–if you know it.
But suppose the safe is on the other side of town. He tortures you for the combination. You give him a combination, and he leaves. Then you call the cops, or get your gun, or whatever. In this case, torture is guaranteed not to work, because you can say anything, and there’s no way for the torturer to check the truth.
And this is why torture under a “ticking time bomb” scenario is guaranteed not to work. Because you torture the guy until he tells you where the bomb is, and you race to defuse the bomb, only to find that the bomb wasn’t there, and then the real bomb goes off.
And this is why open-ended interrogations often fail.
“Who do you work for?”
“Uh…Bob.”
“Liar!” [tortures]
“Wait, stop, it’s Steve!”
“Liar!” [tortures more]
“Crap, I mean Bill!”
“Liar!” [tortures more]
“I mean, it really is Steve! I was lying about Bill, but was telling the truth about Steve!”
“Seriously?” [tortures more]
“Yes!”
“Really? Wow, I guess I’ll stop torturing you now.”
“That’s a relief.”
Now, when did the suspect tell the truth? If any?
This could work if the situation is analogous to the “safe in the room” scenario. The cops have you in custody, and can go check out Steve at their leisure, and can come back a few days later with other evidence either for or against Steve, and can resume torture if they think you lied.
But what happens if they grab Steve, and start to torture him to confess, and since you fingered Steve, they torture him until he confesses to working with you? And now they know you told the truth, because Steve confessed. Surely you see the problem here. They know Steve is guilty because they tortured you until you implicated Steve, and they know Steve is guilty because they tortured him until he confessed, and they confirmed that you’re guilty because Steve implicated you. And so on.