One of the problems with the advocacy of torture is that it highlights the lack of training in effective investigation techniques that can corrupt any investigation.

Merle L. Pribbenow, is a 27-year veteran of the CIA's clandestine Directorate of Operations. Writing in Studies in Intelligence, the CIA's in-house journal, he stated:

"If you talk to people who have been tortured, that gives you a pretty good idea not only as to what it does to them, but what it does to the people who do it," he said. "One of my main objections to torture is what it does to the guys who actually inflict the torture. It does bad things. "

He comments "..I have talked to a bunch of people who had been tortured who, when they talked to me, would tell me things they had not told their torturers, and I would ask, 'Why didn't you tell that to the guys who were torturing you?' They said that their torturers got so involved that they didn't even bother to ask questions."

Ultimately, he said "torture becomes an end unto itself."

Here is a report, which shows, in a completely different context (investigation of child abuse) the impact of the use of coercive interview techniques:

how poor investigation techniques can contaminate an interview process