The victims' family members, first responders and survivors will release a statement Friday calling on Biden to skip 20th-anniversary events in New York and Shanksville, Pennsylvania, and at the Pentagon unless he releases the documents, which they believe implicate Saudi officials in supporting the acts of terrorism. The group says that as a candidate Biden pledged to be more transparent and release as much information as possible but that his administration has since then ignored their letters and requests.
"We cannot in good faith, and with veneration to those lost, sick, and injured, welcome the president to our hallowed grounds until he fulfills his commitment," they wrote in a statement obtained by NBC News.
"Since the conclusion of the 9/11 Commission in 2004 much investigative evidence has been uncovered implicating Saudi government officials in supporting the attacks," the statement says. "Through multiple administrations, the Department of Justice and the FBI have actively sought to keep this information secret and prevent the American people from learning the full truth about the 9/11 attacks."
Among the documents the group seeks are supporting evidence found during a widespread FBI investigation into the attacks that examined alleged Saudi links and was completed in 2016.
Brett Eagleson, whose father, Bruce, died at the World Trade Center, said he and his co-signers "collectively are at our wits' end with our own government."
"We are frustrated, tired and saddened with the fact that the U.S. government for 20 years has chosen to keep information about the death of our loved ones behind lock and key," said Eagleson, who is among a group of victims' relatives who filed a federal lawsuit accusing Saudi Arabia of being complicit in the attacks.
While the 9/11 Commission report found that Saudi Arabia had been a "problematic ally," particularly when it came to sharing intelligence, the investigation found no evidence implicating Saudi leaders in the attack.
"The Commission staff found no evidence that the Saudi government as an institution or as individual senior officials knowingly support or supported al Qaeda; however, a lack of awareness of the problem and a failure to conduct oversight over institutions created an environment in which such activity has flourished," the report said.
It did, however, identify Saudi nationals as a major source of funding for Al Qaeda. The Saudi government has denied any connection to the attacks.
Eagleson said he is convinced that senior leaders in the Saudi government knew about the planned attack and did nothing to stop it.
Among the evidence he cites is the 2017 sworn testimony of former FBI Special Agent Stephen Moore, who was in charge of the Los Angeles Task Force Team for PENTTBOM, the FBI's investigation of the 9/11 attacks.
"Based on evidence we gathered during the course of our investigation, I concluded that diplomatic and intelligence personnel of the Kingdom of Saudi Arabia knowingly provided material support to the two 9/11 hijackers and facilitated the 9/11 plot. My colleagues in our investigation shared that conclusion," Moore said in his affidavit.
The administrations of George W. Bush, Barack Obama and Donald Trump also declined to declassify supporting documents, citing national security concerns. The Trump administration invoked the state secrets privilege in 2019 to justify keeping documents classified.
"Twenty years later, there is simply no reason — unmerited claims of "national security' or otherwise — to keep this information secret," the group wrote. "But if President Biden reneges on his commitment and sides with the Saudi government, we would be compelled to publicly stand in objection to any participation by his administration in any memorial ceremony of 9/11."
Eagleson said in an interview, "The buck stops at the president."
After this story was published, a Biden administration source familiar with the matter said the Justice Department is expected to begin a review of the documents to determine whether any can be released. The review will include documents in which states secrets or law enforcement privilege have been cited as grounds for keeping the information classified.
While the goal is a quick review, it is not likely to be completed before the 20th anniversary of the attacks this year, the source said.