WASHINGTON -- The secrecy surrounding the National Security Agency's surveillance and bulk data collection program after Sept. 11, 2001, hampered its effectiveness, and members of the intelligence community later struggled to identify any specific ways it had thwarted potential terrorist attacks, a newly declassified document shows.

The document is a lengthy report on a formerly secret NSA program code-named StellarWind. The report was a joint effort in 2009 by inspectors general for five intelligence and law enforcement agencies. The full report was withheld from the public at the time, although a short version was made public.

The government released a redacted version of the full report to The New York Times on Friday in response to a Freedom of Information Act lawsuit.

The report amounts to a history of the program. Although some significant parts remain classified, it includes some new details. For example, it explains why the administration of President George W. Bush told the chief judge of the Foreign Intelligence Surveillance Court at the time of the Sept. 11 attacks, Royce Lamberth, about the program's existence in early 2002.

James Baker, the Justice Department's top intelligence lawyer at the time, was not told about the program. But he came across "strange, unattributed" language in an application for an ordinary surveillance warrant and figured out that something unusual was happening, and he then insisted on telling Lamberth. Baker is now the general counsel to the FBI.

It also says Lamberth and his successor, Judge Colleen Kollar-Kotelly, approved "scrubbing" procedures to use information from StellarWind, which the Foreign Intelligence Surveillance Court had not approved as legal, in applications for regular warrants issued by that court to wiretap Americans on American soil for national-security investigations.

In 2004, Kollar-Kotelly also told the department that it could not include an American's phone number or email address in its applications for ordinary warrants if that same account appeared in reports generated by StellarWind, unless the FBI had independently become interested in that account or could show that it "inevitably" would have.

The secrecy surrounding the program was so intense that the White House would not let Kollar-Kotelly keep a copy of a letter written by a Justice Department lawyer, John Yoo, explaining why the program was legal. The White House also rejected Attorney General John Ashcroft's request to tell his deputy, Larry Thompson, about it.

After Yoo left the government in 2003, the White House selected an aide to Ashcroft, Patrick Philbin, to be the attorney general's legal adviser for the program. Philbin read Yoo's memos and concluded that his reasoning was flawed.

Among other things, the report said, Yoo's reasoning was premised on the assumption that the Foreign Intelligence Surveillance Act did not expressly apply to wartime situations, but Yoo's memo -- most of which has never been made public -- did not mention that the statute had a provision saying its procedures would not apply for the first 15 days of a new war.

Later that year, the Senate confirmed a new head of the Office of Legal Counsel, Jack Goldsmith, and a new deputy attorney general, James Comey, who is now the FBI director. Vice President Dick Cheney's counsel, David Addington, resisted telling them about the program, and they later became critics of it.

The report discusses an episode in March 2004 when Comey and Goldsmith confronted Alberto Gonzales, then the White House counsel, in the hospital room of Ashcroft, who was ailing, over the legality of the program. That led Bush to make two or three changes to it, the report said. But the details are censored.

Nevertheless, it is public knowledge -- because of a trove of documents leaked by former intelligence contractor Edward Snowden -- that the dispute at least in part concerned the legality of a component of the program that collected bulk records of international emails to and from Americans. Bush agreed to pause the program, which resumed several months later after the department persuaded Kollar-Kotelly to issue an order that she said made it legal.

Snowden's disclosures included a working draft of the NSA inspector general's contribution to this larger report, roughly 50 pages long. The final version of that document -- with many passages redacted as still classified, even though they are not redacted in the version Snowden released -- was part of the release Friday.

The newly disclosed report filled in a missing explanation for a change in FBI rules during the Bush administration. Previously, the FBI had only two types of cases: "preliminary" and "full" investigations. But the Bush administration invented a third, the "threat assessment," later changed to just "assessment."

This development, it turns out, was a result of StellarWind. The NSA was generating information that suggested a potential link to terrorism on domestic soil, and FBI agents were asked to scrutinize those links without being told what the basis for it was. They were instructed to use these "tippers" as leads only and "not to use the information in legal or judicial proceedings."

That made some agents uncomfortable because they were not sure what the information was or how it fit into their rules for investigations. As a result, the Justice Department created the new assessment-type investigation.

But little came of the StellarWind tippers. In 2004, the FBI general counsel's office looked at a sampling of all the tippers it had run down to see how many had made a "significant contribution" to identifying a terrorist, deporting a suspected terrorist or developing a confidential informant who might provide information about terrorists.

Just 1.2 percent of the tippers from 2001-04 made such a contribution. Two years later, the FBI general counsel's office reviewed all the tipper leads generated from the wiretapping component of StellarWind from August 2004 to January 2006 and found that none of them from that period had been useful to the FBI's counterterrorism efforts.

The report included several paragraphs describing cases in which information from StellarWind was a success, but those details were redacted.

A Section on 04/25/2015