But a closer examination shows a more subtle picture. None of the Justice Department lawyers who reviewed the interrogation question argued that the methods were clearly illegal.

For example:

¶Mr. Goldsmith, now a Harvard law professor, unnerved the C.I.A. in June 2004 by withdrawing a 2002 memorandum written by Mr. Yoo that said only pain equal to that produced by organ failure or death qualified as torture.

In addition, in a previously undisclosed letter to the agency, Mr. Goldsmith put a temporary halt to waterboarding. But he left intact a secret companion memorandum from 2002 that actually authorized the harsh methods, leaving the C.I.A. free to use all its methods except waterboarding, including wall-slamming, face-slapping, stress positions and more.

¶Mr. Levin, now in private practice, won public praise with a 2004 memorandum that opened by declaring “torture is abhorrent.” But he also wrote a letter to the C.I.A that specifically approved waterboarding in August 2004, and he drafted much of Mr. Bradbury’s lengthy May 2005 opinion authorizing the 13 methods.

¶Mr. Comey, who had forced a 2004 showdown with White House officials over the National Security Agency’s surveillance program, concurred in that Bradbury opinion. His objections focused on a second legal opinion that authorized combinations of the methods. He expressed “grave reservations” and asked for a week to revise the memorandum, warning Mr. Gonzales that “it would come back to haunt him and the department,” Mr. Comey said in a 2005 e-mail message to Mr. Rosenberg.

Justice Department lawyers involved in the opinions felt torn between what was legal and what was advisable, Mr. Levin said. “Obviously you can only do that which is legal,” he said in a recent interview. “But that does not mean you should automatically do something simply because it is legal.”

Image Jack Goldsmith halted waterboarding but left intact a memorandum authorizing the methods.

The e-mail messages and documents provide new details about a critical year in the interrogation saga, beginning in mid-2004. The C.I.A. inspector general had questioned the legality and effectiveness of the harsh methods, prompting a review of the program. Under intense White House pressure, the Justice Department lawyers in May 2005 approved a series of opinions that reauthorized the harshest practices.