Joe Biden’s campaign issued a rare and defensive memo Monday on the eve of the release of Amazon’s “most anticipated” nonfiction book—Profiles in Corruption: Abuse of Power by America’s Progressive Elite by Government Accountability Institute President and Breitbart News contributor Peter Schweizer.

In the memo, Biden’s campaign demanded media outlets explicitly state the former vice president engaged in no “wrongdoing” when reporting on actions he took in 2016 urging Ukraine to fire its top prosecutor.

“It is not sufficient to say that allegations are ‘unsubstantiated’ or that ‘no evidence has emerged to support them,'” the campaign wrote. “Not only is there ‘no evidence’ for Republicans’ main argument against the [former] vice president there is a mountain of evidence that actively debunks it.”

As has been widely noted, the prosecutor at the time was investigating Burisma Holdings, a Ukrainian natural gas conglomerate upon whose board of directors Hunter Biden sat.

Given the extensive nature of the younger Biden’s wheeling and dealing in Ukraine, many have speculated the former vice president intervened in hopes of squashing the investigation into Burisma. That notion has been mostly notably advanced by John Solomon, a former reporter for the Hill.

Biden’s campaign, however, went further by alleging in its memo that Solomon received help in “spreading” the theory from “Breitbart editor Peter Schweizer.”

The campaign’s claims involving Schweizer are not backed up by facts. Although Schweizer, who is a senior contributor at Breitbart News, was the first to expose Hunter Biden’s lucrative dealings in Ukraine in his bestseller—Secret Empires—he did not link the prosecutor’s ouster with any attempts at obstructing justice. It is also unlikely such a theory about Biden’s motives would have been included, since Secret Empires, like most of Schweizer’s books, relies on primary sources such as tax documents and legal filings to back up its findings.

The suggestion otherwise comes one day after the New York Post ran a lengthy excerpt from Schweizer’s new book, Profiles in Corruption, detailing how five members of the Biden family got rich off the former vice president’s political influence.

Profiles, which has already hit number one on Amazon, will be released Tuesday to much fanfare. As the excerpt suggests, the book will have explosive implication for a number of progressive leaders, but likely none more so than Biden.