Correction: An earlier version of this story misidentified the board on which Kenneth Wainstein sits. The story has been corrected.

Colleen Kollar-Kotelly provided the legal foundation for the NSA amassing a database of all Americans’ phone records, say current and former officials who have read it. (AP)

In the recent stream of disclosures about National Security Agency surveillance programs, one document, sources say, has been conspicuously absent: the original — and still classified — judicial interpretation that held that the bulk collection of Americans’ data was lawful.

That document, written by Colleen Kollar-Kotelly, then chief judge of the Foreign Intelligence Surveillance Court (FISC), provided the legal foundation for the NSA amassing a database of all Americans’ phone records, say current and former officials who have read it.

Now, more officials are saying that Americans should be able to read and understand how an important precedent was established under the 2001 USA Patriot Act, which was passed after the Sept. 11, 2001, attacks.

“The original legal interpretation that said that the Patriot Act could be used to collect Americans’ records in bulk should never have been kept secret and should be declassified and released,” Sen. Ron Wyden (D-Ore) said in a statement to The Washington Post. “This collection has been ongoing for years and the public should be able to compare the legal interpretation under which it was originally authorized with more recent documents.”

Kollar-Kotelly told associates this summer that she wanted her legal argument out, according to two people familiar with what she said. Several members of the intelligence court want more transparency about the court’s role to dispel what they consider a misperception that the court acted as a rubber stamp for the administration’s top-secret spying programs. The court meets in secret to hear applications for domestic surveillance and its opinions generally are not made public.

Kollar-Kotelly, who is no longer on the FISC, declined to comment, as did the current chief judge, Reggie B. Walton.

Kollar-Kotelly’s interpretation served as the legal basis for a court authorization in May 2006 that allowed the NSA to gather on a daily basis the phone records of tens of millions of Americans, sources say. Her analysis, more than 80 pages long, was “painstakingly thorough,” said one person who read it. The date of the analysis has not been disclosed.

The broad outlines of the judge’s argument have been revealed via a Justice Department “white paper.” And last month, the administration released a 29-page opinion written in August that defended the program by asserting essentially that as long as some Americans’ phone records might be “relevant” to a terrorism investigation, the government may collect them all. But that opinion, current and former officials said, is not a substitute for Kollar-Kotelly’s original interpretation.

“If the question is, ‘How was this program authorized and what type of legal analysis first took place?’ the 2013 opinion is just not responsive,” said one former senior Obama administration official. “It’s hard for me to imagine, with all that’s already out there, that highly classified intelligence material would be so deeply entwined in the legal analysis in that original interpretation that they couldn’t somehow release it.”

Asked to comment, Justice Department spokesman Brian Fallon said, “Already so far, the department has declassified a white paper explaining the legal basis for the [phone records] program, and the court has publicly posted an opinion upholding its lawfulness.” He declined to confirm or deny the existence of Kollar-Kotelly’s original interpretation.

According to a draft NSA inspector general report obtained by The Post from former NSA contractor Edward Snowden, Kollar-Kotelly in 2004 approved the NSA’s collection of Americans’ bulk e-mail metadata records (to-from addresses, dates, time stamps, etc.) using a Patriot Act provision similar to one the court used in 2006 to authorize the phone records program. The argument made for the e-mail metadata program, analysts say, may have been used to justify the phone records collection.

The phone program logs metadata such as numbers called and the time and duration of calls but not names or content.

Fallon said that “additional materials related to the [phone] program are under review for possible declassification and release” in response to lawsuits by the American Civil Liberties Union and the Electronic Frontier Foundation. The original interpretation is one of a number of classified court documents and executive branch rulings that some lawmakers say should be declassified.and released

Government lawyers have told the ACLU that they are withholding at least two significant FISC opinions — one from 2008 and one from 2010 — relating to the Patriot Act’s Section 215, or “business records” provision.

Fallon declined to comment.

The Justice Department also is reviewing a 2006 court opinion related to the Section 215 provision to determine whether it can be released, said Alex Abdo, an ACLU staff lawyer. (A senior department official told The Post that no 2006 Kollar-Kotelly opinion is based on that provision.)

Kenneth Wainstein, a former senior Justice Department official now on the Public Interest Declassification Board, an advisory committee established by Congress, agreed that more disclosure is wise. “Especially when it comes to legal decisions about big programs,” he said at a recent panel discussion sponsored by the New York University School of Law, “we can talk about them in a sanitized way without disclosing sources and methods.”

Senate Judiciary Committee Chairman Patrick J. Leahy (D-Vt.) said in a statement to The Post that he is “particularly interested” in seeing the administration declassify and release “any additional legal analysis” related to the phone records program. “That,” he said, “is exactly the sort of transparency we need in order to have a full and open debate about whether this program is legal and appropriate or needed.”