Lawyers Showed Photos of Covert CIA Officers to Guantanamo Bay Detainees

Romero said he does not know what laws the government thinks the military lawyers may have broken.

"That is the most vexing part of it," he said. "Usually when you're read your Miranda rights or visited by the Justice Department or the FBI, you are given some indication as to what laws are at stake."

The National Association of Criminal Defense Lawyers also declined to address the specifics of the inquiry but questioned its timing.

It is "customary in our experience that any kind of investigation like these are conducted after legal proceedings are finished in the case so as not to interfere with the defense function, not to interfere with the rights of defendants, not to give the appearance that the government is looking to chill the defense function," said Joshua L. Dratel, counsel for the John Adams Project and a former board member of the NACDL, who spoke on behalf of the group.

He added: "The lawyers have a duty to find out what happened to their clients, and to the extent that the government and certain agencies are resistant to that to protect themselves and to insulate themselves from accountability, there is a tension there, and to the extent that this investigation is part of that tension, it's most unfortunate. But the lawyers will not shirk their duty."

A wide variety of groups, including European investigators, human rights groups and news organizations, have compiled lists of people thought to have been involved in the CIA's program, including CIA station chiefs, agency interrogators and medical personnel who accompanied detainees on planes as they were moved from one secret location to another.

"It's a normal part of human rights research projects, and certainly in defense work, to compile lists of individuals who interacted with clients," Romero said.

Tracking international CIA-chartered flights, researchers have identified hotels in Europe where CIA personnel or contractors stayed. In some cases, through hotel phone records, they have been able to identify agency employees who jeopardized their cover by dialing numbers in the United States. Working from these lists, some of which include up to 45 names, researchers photographed agency workers and obtained other photos from public records, the sources said.

The government has largely cut off the airing of details about the CIA's interrogation program during proceedings at Guantanamo Bay, although many have been revealed in government documents.

At the courthouse at the prison, a court security officer, who is thought be in contact with CIA officials, can cut off the audio feed to the public gallery if there is any possibility of lawyers or defendants discussing CIA detention. At a hearing in July, the audio feed was cut when a lawyer for Ramzi Binalshibh, one of the alleged Sept. 11 conspirators, mentioned sleep deprivation, one of the "enhanced interrogation techniques" used at the CIA's black sites.