The president has finished a review first mandated by law in 1992, and while a vast majority of papers related to the assassination of President John F. Kennedy have been released, some remain redacted.

Peter Baker, the chief White House correspondent, last wrote about the John F. Kennedy assassination papers during the Trump administration.

July 16, 2023

On June 22, 1962, an intelligence official drafted a memo summarizing a letter intercepted between Lee Harvey Oswald and his mother. The memo was made public long ago. But for 60 years, the name of the letter opener was kept secret.

Now it can finally be told: According to an unredacted copy of the memo released recently by the government, the official who intercepted Oswald’s mail for the C.I.A. in the months before President John F. Kennedy was assassinated was named Reuben Efron.

And that means — what, exactly? A tantalizing clue to unraveling a complicated conspiracy that the government has sought to cover up for decades? Additional proof that the C.I.A. knew more about Oswald than initially acknowledged? Or a minor detail withheld all this time because of bureaucratic imperatives irrelevant to the question of whether Oswald was the lone gunman on the fateful day?

The mystery of Reuben Efron, who has been dead for three decades, may never be resolved to the satisfaction of some of those dedicated to studying the assassination. Thirty years after Congress ordered that papers related to the killing be made public with limited exceptions, President Biden has declared that he has made his “final certification” of files to be released, even though 4,684 documents remain withheld in whole or in part. Going forward, agencies will decide any future disclosures that may be warranted by the passage of time.

The president’s certification, issued at 6:36 p.m. on the Friday before the long Fourth of July holiday weekend, when it would not draw much attention, has frustrated researchers and historians still focused on the most sensational American murder of the 20th century. But they suffered a setback on Friday when a federal judge refused to block Mr. Biden’s order.

Jefferson Morley, the editor of the blog JFK Facts and the author of several books on the C.I.A., said the belated identification of Efron indicated that intelligence agencies still had something to keep from the American public.

“If they hid this guy’s name for 61 years and they’re still hiding other stuff, I would say they’re still hiding sources and methods around Oswald,” Mr. Morley said. “Why else did the name remain secret for 61 years? The C.I.A. is trying to slam the door now, and Biden’s gone along with this.”

From the other side of the spectrum, Gerald Posner, the author of “Case Closed,” a 1993 book concluding that Oswald killed Kennedy on his own, said he doubted there was a smoking gun in the remaining files.

“Everyone is focused on the C.I.A. documents still withheld,” he said. “What we have learned from the C.I.A. files released this year is that they either have nothing to do with the assassination, or are only tangentially related.”

While he and Mr. Morley diverge on the historical evidence, Mr. Posner agreed that Mr. Biden’s decision was “an abrogation of responsibility under the 1992 law” mandating release of the documents. Trust in the government being what it is, he said, the public will never accept official reassurances that there is no stunning revelation in the papers.

“I don’t think that’s there,” he said, “but you’ll only know when you have all the files available.”

The intense interest in Kennedy conspiracy theories prompted Congress to pass the 1992 law mandating that documents related to the assassination be released within 25 years except those that could do “identifiable harm” to national security that outweighs the value of disclosure. When the deadline arrived in 2017, President Donald J. Trump, who has dabbled in conspiracy theories about the assassination himself, bowed to pressure from intelligence agencies to grant more time. After taking office, Mr. Biden signed two memos doing the same.

Of roughly 320,000 documents reviewed since the law passed, 99 percent have been disclosed, according to the National Archives and Records Administration. But 2,140 documents remain fully or partially withheld as a result of Mr. Biden’s action, officials said, while another 2,502 remain withheld for reasons outside the president’s purview, like court-ordered seals, grand jury secrecy rules, tax privacy limits or restrictions imposed by people who donated papers, and 42 for a mix of both.

A vast majority of excluded documents have actually been released but with certain parts redacted, officials said, including names of people still living, addresses, telephone or Social Security numbers, or locations of intelligence facilities. Officials said they were confident that none of the withheld information would change the essential understanding of the assassination.

While Mr. Biden’s June 30 order means he is done, the archives and agencies have set up “transparency plans” so remaining redactions can be lifted in the future, such as upon the death of someone whose identity was protected.

The Mary Ferrell Foundation, an organization already suing the government over the files, sought an injunction against Mr. Biden after his latest order. But Judge Richard Seeborg of the Federal District Court in Northern California rejected it on Friday night and dismissed other parts of the original lawsuit, though he allowed some claims to proceed.

Lawrence Schnapf, a lawyer for the foundation, denounced Mr. Biden’s action. “It is simply unfathomable to me that a man who has a bust of R.F.K. in his office and who voted for the law would cave in to the incredulous claims of the national security bureaucracy that 60-year-old records pose such a risk to national security that they cannot be released,” he said.

The Justice Department declined to comment but maintained in its filings that the government had complied with the law. The C.I.A. did not respond to requests for comment. “This completes the review of records required by Congress and fulfills the president’s commitment to maximizing transparency related to President Kennedy’s assassination,” said Adam Hodge, a spokesman for the White House.

The assassination still has enormous power to arouse suspicion. Robert F. Kennedy Jr., who has embraced conspiracy theories on vaccines and other matters and is now challenging Mr. Biden for the Democratic presidential nomination, said recently that the government had orchestrated a “60-year cover-up” in his uncle’s killing.

“There’s overwhelming evidence that the C.I.A. was involved in his murder,” he told the radio host John Catsimatidis in May. “I think it’s beyond a reasonable doubt at this point.”

Mr. Trump, for his part, vowed to do in a second term what he did not in his first. “I released a lot, as you know. And I will release everything else,” said in an interview in May with The Messenger, a new online news site.

The final 1,103 documents released days before Mr. Biden’s order and those made public in preceding months offered new information that hardly seemed worth keeping cloaked so long. In April, for instance, a file was released with names of employees in the C.I.A.’s Mexico City station, mostly secretaries and translators. Another document listed 27 previously unreleased C.I.A. staff members’ names; for whatever it is worth, the C.I.A. director John McCone’s secretaries were named Marguerite Beard, Betty Davis and June Irish.

Whether any of the withheld documents would shed more light on Reuben Efron is unknown. His name on the mail intercept memo intrigued Mr. Morley. The memo was sent to Betty Egerter at a C.I.A. unit known as “the office that spied on spies.” On the day of the assassination, Egerter’s boss told the F.B.I. that the C.I.A. had no information on Oswald, who in fact had been monitored when he moved to the Soviet Union. A document released long ago showed that the agency opened Oswald’s correspondence from Nov. 11, 1959, to May 1, 1960, and again from July 1, 1961, to May 25, 1962.

Curiously, Efron was previously listed as being in the room when the Warren Commission interviewed Marina Oswald, his Russian-born widow, in February 1964 — the only one present whose title and role were not explained. Mr. Morley suspects Efron was monitoring the commission’s investigation for James Angleton, the legendary C.I.A. official, essentially his “eyes and ears inside the room.”

Efron was born in Lithuania in 1911 as Ruvelis Effronas and arrived in the United States via Cuba in 1939, according to immigration papers that described him as a 5-foot-3, 135-pound “merchant-salesman.” In addition to English, he spoke Russian, Lithuanian, Hebrew, Yiddish and German, and served in the Air Force during World War II as an interpreter. His obituary said that after the war he was “a specialist on the Soviet Union and consultant on foreign affairs” without saying for whom.

In a harmonic convergence of conspiracy, Efron reported seeing a U.F.O. in 1955. He was traveling with Senator Richard Russell, Democrat of Georgia, and an Army colonel on a train trip through the Soviet Union when all three spotted what a C.I.A. report called two “flying saucers.” Skeptics later suggested they were Soviet aircraft. Russell was among the Warren Commission members in the room for the Marina Oswald interview that Efron attended in 1964.

As it happened, Efron died on Nov. 22, 1993 — the 30th anniversary of the Kennedy assassination. His wife has died too, and he had no known children. Efforts to reach other family members were unsuccessful.

“People say there’s nothing significant in these files?” Mr. Morley said. “Bingo! Here’s the guy who was reading Oswald’s mail, a detail they failed to share until now. You don’t have to be a conspiracy theorist to think it’s suspicious.”

Mr. Posner finds it less suspicious but understands why others might. “Many of us have made up our minds,” he said. “Some of us have made up our minds that there was a conspiracy, and some of us have made up our minds that it was Oswald.

“But in the end, we all want to see these files.”