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In October 2007, Attorney General nominee Michael Mukasey drew criticism for his refusal to characterize water boarding, a controversial interrogation technique considered by many to be illegal, as torture. Mukasey, a retired federal judge nominated by President Bush, dodged the question in his confirmation hearing by the Senate Judiciary Committee, stating that "if [water boarding] amounts to torture, it is not constitutional," but never explicitly condemning it [source: NPR]. His response prompted several senators on the committee to declare that they would oppose Mukasey's nomination as Attorney General unless he denounces water boarding as a form of torture.

Win McNamee/Getty Images Attorney General nominee Michael Mukasey came under fire for refusing to classify water boarding as torture.

Mukasey's nomination wasn't the first time the Bush administration faced controversy over what it considered appropriate interrogation techniques of terror suspects. In an October 2006 radio interview, Vice President Dick Cheney was asked if a "dunk in the water" was an acceptable form of prisoner interrogation. When he answered in the affirmative, many people took that to be an endorsement of water boarding. Human rights groups immediately seized on the statement as indicating support for torture, and Cheney's spokespeople released statements saying that Cheney was not endorsing water boarding when he made that remark.

Water boarding has been around for centuries. It was a common interrogation technique during the Italian Inquisition of the 1500s and was used perhaps most famously in Cambodian prisons during the reign of the Khmer Rouge regime during the 1970s (see David Corn: This Is What Waterboarding Looks Like for pictures of a Khmer Rouge water board now in a Cambodian museum). As late as November 2005, water boarding was on the CIA's list of approved "enhanced interrogation techniques" intended for use against high-value terror suspects. In a nutshell, water boarding makes a person feel like he is drowning.

Water boarding as it is currently described involves strapping a person to an inclined board, with his feet raised and his head lowered. The interrogators bind the person's arms and legs so he can't move at all, and they cover his face. In some descriptions, the person is gagged, and some sort of cloth covers his nose and mouth; in others, his face is wrapped in cellophane. The interrogator then repeatedly pours water onto the person's face. Depending on the exact setup, the water may or may not actually get into the person's mouth and nose; but the physical experience of being underneath a wave of water seems to be secondary to the psychological experience. The person's mind believes he is drowning, and his gag reflex kicks in as if he were choking on all that water falling on his face.

So what do intelligence professionals think of this technique? Read on to find out.