— The Obama administration and the Senate Intelligence Committee are sparring over the administration's deletions of fake names from the public version of a long-awaited report on the CIA's use of harsh interrogation methods on suspected terrorists, McClatchy has learned.

The outcome of the debate could impact the clarity and narrative flow of the report, the product of the most intensive congressional investigation of CIA operations since lawmakers examined the agency's role in the Iran-Contra arms-for-hostages scandal of the Reagan presidency.

"Redactions are supposed to remove names or anything that could compromise sources and methods, not to undermine the source material so that it is impossible to understand," Sen. Martin Heinrich, D-N.M., a member of the committee, said Sunday in a statement. "Try reading a novel with 15 percent of the words blacked out. It can't be done properly."

The blackouts have added fuel to what already were serious tensions between the CIA and its congressional overseers over the report and the agency's admission last week that its personnel had broken into a computer database that by agreement was for the exclusive use of committee staffers.

In his statement, Heinrich didn't identify the nature of the deletions made in a months-long declassification process in which the CIA and then the White House blacked out from the executive summary what they deemed to be sensitive national security information. The 480-page executive summary, findings and conclusions are the only part of the full 6,600-page top-secret report that are to be made public

But Tom Mentzer, a spokesman for the committee's chairwoman, Sen. Dianne Feinstein, D-Calif., told McClatchy on Monday that the blackouts _ officially known as redactions _ were made to pseudonyms used for both covert CIA officers and foreign countries.

"No covert CIA personnel or foreign countries are named in the report," he said. "Only pseudonyms were used, precisely to protect this kind of information. Those pseudonyms were redacted (by the administration)."

All of the pseudonyms were excised from the version of the executive summary that the White House returned to the committee on Friday, a person familiar with the issue said.

Lawmakers seem willing to accept some redactions, but others made by the CIA and the White House would make it difficult or impossible to understand the subject being discussed, especially when a pseudonym appears in multiple references, said the knowledgeable person, who requested anonymity because of the matter's sensitivity.

The CIA declined comment.

A second knowledgeable individual, also speaking on condition of anonymity because of the matter's sensitivity, defended the redactions, saying that the true identities of undercover CIA officers could be discerned by piecing together all of the information in the report associated with specific pseudonyms.

"A pseudonym of a person could reveal information streams about where that person was and what that person did that could result in that person being identified," said the second knowledgeable individual. "And that could result in harm against that person. A fake name is not a silver bullet for protecting someone."

The pseudonyms for foreign countries that were involved in some way with the CIA program _ in which suspected terrorists were abducted and confined and interrogated in secret overseas prisons _ apparently were redacted for the same reasons.

Revealing the names of countries that cooperated could jeopardize important intelligence-sharing relationships, embarrass governments and trigger domestic political backlashes.

A former federal official familiar with the contents of the report said that he was skeptical of the need to excise all pseudonyms, saying such extensive deletions would harm the public's ability to understand what occurred.

"The story is partly about names and places. All of a sudden you wouldn't be able to tell that story," said the former federal official, who spoke on condition of anonymity because of the sensitivity of the issue. "Essentially it just becomes a bunch of verbs. 'Something was done but nobody did it and it wasn't done anywhere.' It's similar to 'Mistakes were made.' There's no accountability in the narrative. It would make it incomprehensible."

White House spokesman Josh Earnest justified the redactions, telling reporters: "We're talking about very sensitive information here. And it's important that a declassification process be carried out that protects sources and methods and other information that is critical to our national security."

He noted that more than 85 percent of the executive summary wasn't blacked out.

"There was a good-faith effort that was made by the administration and by national security professionals to evaluate this information and to make redactions that are consistent with the need to protect national security, but also consistent with the president's clearly stated desire to be as transparent as possible about this," he said.

Earnest left open the door to negotiations with the committee over the extent of the redactions.

"This administration and the relevant national security agencies have indicated a willingness to sit down with those who have spoken out about this just in the last couple of days to try to find some common ground here and satisfy their concerns so that we can get this report released as quickly as possible," he said.

In a statement issued on Friday, Feinstein said that the "significant redactions" made to the executive summary would delay its release "until further notice" while the committee evaluated their impacts. Several hours later, Director of National Intelligence James Clapper defended the deletions, saying that they involved less than 15 percent of the document and that half of the blackouts were made to footnotes.

The report's findings are scathing, concluding that the CIA's use of waterboarding and other harsh interrogation methods on suspected terrorists under the George W. Bush administration had produced little valuable intelligence that couldn't have been gleaned with traditional techniques. Some current and former U.S. officials and military commanders, as well as legal experts and foreign governments, have denounced the techniques as torture.

The report also found that the agency misled the Bush administration, Congress and the public about the effectiveness of the interrogation methods, and it questioned the legal justifications for allowing the interrogation program, according to the report's conclusions obtained by McClatchy in April.

The CIA and former Bush administration officials dispute the report's conclusions and deny that the harsh interrogation techniques constituted torture.

Marisa Taylor of the Washington Bureau contributed.

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