Thousands of documents pertaining to former Vice President Joe Biden’s 40-year career in the U.S. Senate are unlikely to become public until after the 2020 election.

On Friday, the Washington Post reported that a collection of documents Biden donated to the University of Delaware will not be made accessible until December 2019 or “two years” after the former vice president “retires from public life.” When the documents were initially donated in 2011, the university agreed to keep them sealed “for two years after Biden retires from public office.”

Those parameters appear to have changed. On 24 April, the day before Biden declared his presidential run, the university announced the trove of documents would not be made public until two years after Biden “retires from public life” or after Dec. 31, 2019, whichever comes later. The university has provided no definition for what is considered “public life,” according to the Post.

“The entire collection is unavailable,” Andrea Boyle Tippett, a spokeswoman for the university, said. “Its contents will become available… when Mr. Biden retires from public life.”

“As he is currently running for office, he is in public life,” Tippett added. “Since retirement for anyone, not just public figures, takes different forms, I can’t speculate beyond that.”

It appears unclear to what extent Biden’s team is involved in the changing deadline.

“The Biden campaign said no change has been made to the agreement since September 2016, although it could not say what change was made then,” the Post reported. “The campaign said it had nothing to do with the change announced by the university in April.”

The documents, which purportedly fill 1,875 boxes and include 415 gigabytes of electronic records, span the length of Biden’s tenure in the U.S. Senate from 1973 through 2009. Included within the trove of documents are “committee reports, drafts of legislation,” and personal correspondance between Biden and his colleagues.

Portions of the documents are likely to be controversial, especially those detailing Biden’s work with segregationists to oppose the use of busing integrate public schools in the 1970s. In recent weeks, the former vice president has been under fire after praising the “civility” of two of his allies in that fight, the late-segregationist Sens. James Eastland (D-MS) and Herman Talmadge (D-GA).

The issue came to a head at the Democrat presidential debate last month, when Sen. Kamala Harris (D-CA) confronted Biden over the remarks and his longstanding views on busing.

“I agree with you when you commit yourself to the importance of finding common ground,” Harris said, “but I also believe and it’s personal and it was hurtful to hear you talk about the reputations of two United States senators who built their reputations and career on the segregation of race in this country.”

“It was not only that, but you also worked with them to oppose busing,” she continued. “There was a little girl in California who was part of the second class to integrate her public schools and she was bussed to school every day. That little girl was me. So I will tell you that on this subject, it cannot be an intellectual debate… we have to take it seriously.”

Biden attempted to defend himself, but instead of disputing the claims, the former vice president only muddled his position on busing and inaccurately claimed that he never offered praise for racists.

Apart from Biden’s own mishandling of the situation, the controversy has also refused to die down because of a constant stream of old statements and positions coming to light.

Other portions of Biden’s career, such as those dealing with Clarence Thomas’s confirmation to the Supreme Court and his authoring of the 1994 crime bill, are likely to be controversial as well.

David Brinkely, a noted historian and presidential biographer, told the Post it would not be surprising if Biden’s team had sought to delay the release of the documents.

“They aren’t keen on opening a lot of information when someone is running for office,” Brinkley said. “I wish they were wide open for the public, but alas when politicians start running for the president, they try to make sure there’s not that kind of transparency or documentation.”

“The Biden papers will be a great boon for scholars of American political history in the 20th and 21st century,” he added. “There will be notes on Anita Hill, segregation, busing and on and on. . . . Just seeing what the incoming was into his office, and seeing copies of letters Biden wrote in response — it’ll be a rich trove.”