The person being tortured will tell you anything he thinks will stop the pain.
For what crimes should torure of the non-participants be allowed? Rape? Murder? Jaywalking? Theft? Smoking in a car with a baby on board?
It probably has, but it won't be publicized. It also depends what is under the rubric of torture. Use of drugs and other mind altering substances? Retribution against loved ones? Pain? The bottom line is it depends on the individual and the methods used. Almost anyone can be broken.
Lenny Bruce had a routine about a man who is brought to a room where he proclaims that he would never betray his country. Then he says (I'm paraphrasing from memory), "What are they doing to that guy over there? Why are they putting that funnel in his ass? What are they doing with that molten lead? They're pouring it in the funnel? The funnel that's in his ass? They're pouring hot lead in his ass? They're giving him a hot lead enema? Okay, I'll tell you anything. I'll tell you about my mother. I'll make up secrets."
I heard a variation where Bruce says that when faced with the hot lead enema, he would make a shoe shine rag out of the American flag.
Yeah fine...outlaw torture. Feel good about ourselves that we are suicidally principled. The first real instance of a nuclear bomb ticking in an American city, and the chance to extract the location from a smug terrorist sneering in our kumbuya faces - this law will be chucked out the window, along with the authors.
The THREAT of torture is probably more important than actual torture. If we completely outlaw torture, then there is no subsequent threat of torture. Not that I know one thing about torture, but I do know people.
Spare the rod, spoil the child.
Inflicting pain on the flesh has it's own rewrds.
At every level.
There is a vast difference between Ho Chi Minh's thugs torturing John McCain just for the sake of torturing him along with their other prisoners,
and American operatives or allies using rough techniques to extract information that will prevent thousands, hundreds of thousands, even millions of others from being killed.
Mitch Rapp uses it to good effect.