The report by the Justice Department’s inspector general reportedly clears the FBI of wrongdoing in its application for surveillance warrants on Trump adviser Carter Page.

The report, due to be released Dec. 9, found an attorney altered a document in the application for the Foreign Intelligence Surveillance Act warrant on Page, who was acting as an adviser to President Trump’s 2016 campaign, but the action did not affect the validity of the application, the Washington Post reported Friday, quoting people familiar with the report.

CNN reported the former FBI lawyer, described as a low-level line attorney, is under criminal investigation.

Trump sought the Justice Department investigation of the FBI, alleging he had been targeted by the “deep state.” He complained the Obama administration illegally spied on his campaign and demanded the investigation of the FISA application, which he claimed was based on false information.

The FBI, however, had been looking at Page, who had extensive contacts in Russia, before Trump announced his candidacy and sought the warrants as part of its investigation into Russian interference in the 2016 presidential race. The FBI suspected Page of being a Russian intelligence asset, something Page has denied. The FISA application accused Page of “collaborating and conspiring with the Russian government.”

Justice Inspector General Michael Horowitz has been examining the way the FBI conducted its investigation into whether the 2016 Trump campaign colluded with Russian agents. The investigation was taken over by special counsel Robert Mueller after Trump fired then-FBI Director James Comey.

Mueller eventually concluded he did not have enough evidence to charge anyone in the Trump campaign with conspiring with the Russians but that Russian intelligence mounted a concerted effort to interfere with the election process.

Trump supporters have accused the FBI of a variety of violations, claiming the FISA applications were based on opposition research commissioned by Democrats and compiled by a former British spy, what became known as the Steele dossier, which contained salacious allegations about Trump.

Democrats are hoping the Horowitz report will put those theories to rest.

The report is expected to find the FBI made mistakes but did not do anything illegal. Investigators interviewed more than 100 witnesses and reviewed records. The findings were forwarded to Connecticut U.S. Attorney John Durham, a career prosecutor appointed by Attorney General William Barr to head up the investigation.

Horowitz is scheduled to testify about his findings before the Senate Judiciary Committee Dec. 11. The report is expected to be released publicly.