"Pursuing such prosecutions would, we believe, have serious negative effects on the candor with which officials in any administration provide their best advice, and would take our country in a backward-looking direction at a time when our detainee-related challenges demand that we look forward," the letter said.
It went on to say that such prosecutions would have a "seriously chilling effect" on the ability of lawyers to provide legal counsel to the United States.
Adding weight to the letter is its authors' stance on torture. McCain is an outspoken critic of interrogation methods such as waterboarding, having experienced harsh treatment himself. Graham had pushed for greater oversight in detainee interrogation. And the two senators, along with Sen. Carl Levin (D- MI), were responsible for the Detainee Treatment Act, which prohibits inhumane treatment of war prisoners.
The three senators drafted the letter in response to Mr. Obama's statement Tuesday that prosecution of the legal officials is not out of the question. "With respect to those who formulated those legal decisions, I would say that is going to be more of a decision for the attorney general within the parameters of various laws, and I don't want to prejudge that," said the president.
His statement came on the heels of several memorandums that showed that lawyers authorized the use of "enhanced" interrogation techniques by the CIA such as waterboarding, stress positions and exposure to cold during the Bush administration.