Prolonged sleep deprivation, forced nudity and painful body positions are some of the "enhanced interrogation techniques" that the U.S. government approved after Sept. 11, 2001. Three doctors who advocate human rights argue that not only are these methods unethical, but the scientific basis used to validate them was flawed.

The trio, whose policy critique appears today (Jan. 6) in the journal Science, reviewed congressional records and documents from the Department of Justice and the CIA. They found that some of the evidence used to justify enhanced interrogation techniques (EITs) came from studies of U.S. soldiers who underwent SERE training — for "survival, evasion, resistance and escape," exercises that included EITs and were meant to prepare them to survive capture and resist torture. Medical experts involved in those studies, which took place prior to the 9/11 attacks, concluded EITs were "safe, legal and effective," said Scott Allen, a professor of medicine at Brown University and co-author of the critique.

But the training caused dramatic increases in their stress hormone levels and symptoms linked to post-traumatic stress disorder, Allen told LiveScience. Even though the soldiers were allowed to stop the exercises at any time, the stress hormone spikes they experienced were equivalent to that provoked by jumping from a plane or undergoing major surgery, he added.

What’s more, the researchers did not assess the long-term psychological aftermath — a serious failure, Allen said, given that the Justice Department revised the definition of torture in 2002 to include "significant psychological harm of significant duration, e.g., lasting for months or even years."

Phil Zimbardo, a Stanford University professor emeritus who has written about the psychological impact of imprisonment and violence, said, "There are many, many accounts of individuals who suffered very traumatic and enduring effects of the SERE experience, which is nowhere near as extreme as is possible in torture situations." Zimbardo was not involved in the Science policy critique.

Allen said health professionals who oversaw the use of EITs after Sept. 11 were complicit in criminal acts because they failed to intervene or report cases of severe pain or intentional harm. For example, he said, psychologists and psychiatrists did not thoroughly record symptoms of trauma, and they even advised the Department of Defense about using interrogation approaches that could exploit prisoners' vulnerabilities, such as a fear of snakes.

Doctors obligated to care for detainees also violated international standards for documenting the adverse consequences of torture, Allen said.

He has worked with colleagues at Physicians for Human Rights to evaluate 11 detainees released without charge. "They show very high rates of post-traumatic stress disorder, and the anxiety has destroyed their lives," he said. "This really puts a black eye on both the profession and the country."

Moreover, Zimbardo told LiveScience that torture is not an effective way to gather intelligence. Compared with police settings, in which detectives build social rapport and often get confessions without physical force, secret interrogation squads can alienate prisoners and elicit unreliable information, he said.

(For example, a Libyan detainee linked to al-Qaida falsely revealed under torture that there were weapons of mass destruction in Iraq — a key reason for the U.S. invasion of Iraq, Allen said.)

Allen and his collaborators proposed guidelines to help limit the practice of torture. They encouraged military doctors to report all instances of it and to comply with civilian medical ethical standards. They also recommended that government scientists remain separate from the security chain of command, and that independent groups use international regulations to monitor and investigate potential ethical violations by health professionals.

"Scientists who work in the service of the government need enough autonomy so that their work retains integrity and is not unduly influenced by the short-term desired policy goals of the government," Allen said.

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