Do harsh interrogation techniques work (better than the alternatives)?

Over at HUMINT Matt Semel, Visiting Assistant Professor of Criminal Justice, at St. Thomas Aquinas College reviews the new revelations about the Bush Administration's policy on interrogations to see if the claims of waterboarding apologists are supported by the evidence. Do harsh interrogation techniques work?

former FBI special agent Ali Soufan ... wrote in the New York Times that supporters of harsh techniques have yet "to show that the techniques stopped even a single imminent threat of terrorism."
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The vice president has yet to clearly describe how harsh interrogations produced good intelligence or prevented an act of terror.
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The bottom line? We don't know if torture or harsh techniques work and chances are we will never have a definitive answer. There may be cases where harsh techniques actually "work" and succeed in extracting valuable information but this does not mean that rapport building techniques are deficient in comparison.
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If rapport-building techniques and harsh methods work equally well it is axiomatic that the United States not endorse methods proscribed by U.S. law or the Geneva Conventions. To do otherwise diminishes the moral standing of the U.S. and puts our troops in harm's way.
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I have spoken with dozens of interrogators from the Air Force, Army and Marines and most of these experienced interrogators eschew the harsh tactics advanced by President Bush and his administration. They insist that rapport-building methods work best.

Military interrogator Matthew Alexander's "How To Break A Terrorist" comes to a similar conclusion. One can invent numerous hypothetical "what if" situations but in real practice by real interrogators on real information sources, harsh interrogation methods forbidden by the Geneva Conventions which "work" are still not as effective as their less severe and legal alternatives.

We are far from the first people to interrogate our prisoners, and part 2 of Matt's post addresses the history of interrogation in other organizations. He points to Hanns Scharff, acknowledged as "Master Interrogator" by the Marine Corps Interrogator Translator Teams Association for "always treated his prisoners with respect and dignity, and by using psychic not physical techniques" while "magically getting all the answers he needed from the prisoners of war, often with the prisoners never realizing that their words". The MCITTA page on torture is an excellent primer from a source that most will accept as authoritative.