A Senate hearing Tuesday is investigating the origins of aggressive interrogation techniques used by the United States against terrorism suspects.
Officials familiar with the Senate investigation say it shows Pentagon officials began researching the use of harsh techniques against detainees in July of 2002, months before then-Defense Secretary Donald Rumsfeld approved the use of aggressive interrogation methods.
The hearing is expected to reveal that military lawyers questioned the legality of the interrogation techniques before they were used against prisoners in American military custody.
Democratic Senator Carl Levin, head of the Senate Armed Services Committee, says detainee abuse is not the result of rogue soldiers acting on their own. In a statement, he alleged senior U.S. government officials sought out information on aggressive techniques, twisted the law and authorized their use against detainees.
The government has admitted using aggressive interrogation techniques including waterboarding, which simulates the sensation of drowning. Critics have described the harsh methods as torture.
Harsh techniques had been used against detainees at the Abu Ghraib prison in Iraq and the U.S. naval base at Guantanamo Bay, Cuba.
Some information for this report provided by AP.