The Justice Department’s inspector general failed to identify F.B.I. officials who leaked information in 2016 to reporters or to Donald J. Trump’s longtime confidant Rudolph W. Giuliani, who had claimed that he had inside information about an investigation into Hillary Clinton just before the inquiry upended the presidential race, a report released on Thursday said.
The office of the independent inspector general, Michael E. Horowitz, said that it identified dozens of officials who were in contact with the news media and struggled amid such a large universe of contacts to determine who had disclosed sensitive information. It also noted that it had no power to subpoena records, witnesses or messages from officials’ personal communication devices.
Mr. Horowitz had examined the issue after several public disclosures during the election about F.B.I. investigations relating to Mrs. Clinton and Mr. Trump’s campaign.
In one of the most glaring episodes, Mr. Giuliani had claimed on television in late October 2016 that a coming “surprise” would help Mr. Trump. Two days later, the F.B.I. director, James B. Comey, took the highly unusual move of publicly disclosing that the bureau had reopened its investigation into Mrs. Clinton’s use of a personal email account to conduct government business while secretary of state. The revelation jolted the presidential campaign days before Mr. Trump’s unexpected victory.
Later that day, Mr. Giuliani claimed on a radio program that he had heard from former F.B.I. agents and “even from a few active agents, who obviously don’t want to identify themselves,” about rumors of a significant development in the case.
But in the report released on Thursday, Mr. Horowitz’s office said that it had not identified any internal F.B.I. source of information for Mr. Giuliani and that he told investigators that despite his public claims, he had not spoken to “active” agents, only gossiped with former bureau officials.
“He stated that his use of the term ‘active’ was meant to refer to retired F.B.I. agents who were still actively working in security and consulting,” according to the report.
Mr. Giuliani told investigators: “Comey’s statements were a shock to me. I had no foreknowledge of any of them.”
Mr. Giuliani’s 2016 statements have been seen as significant because the inspector general’s office has also found that Mr. Comey disclosed the reopening of the Clinton email investigation in part out of fear that its existence would leak to the news media. A portion of the investigation was being handled by federal authorities in Manhattan, where Mr. Giuliani once served as the U.S. attorney and as mayor, and where he has many longtime friends and supporters in law enforcement.
Mr. Comey later told Congress that he was so concerned about Mr. Giuliani’s comments at the time that he had ordered the bureau to open a leak investigation into who Mr. Giuliani was talking to inside the F.B.I.
Similar to a report published in 2018, the document released on Thursday criticized the F.B.I. for allowing a permissive culture about contacts with the news media in 2016 and for failing to follow its own policies devised to prevent disclosures of sensitive information to the public.
In a sign of the bureau’s culture at the time, the inspector general said that at a conference for F.B.I. special agents in charge of field offices in April 2017, senior bureau officials said that they planned to toughen the policies for dealing with the news media.
“Within hours of this discussion, and months before the F.B.I. officially adopted and announced the new media policy, a national news organization reported on the media policy change discussion at the conference, citing unnamed F.B.I. officials who were in attendance,” the report said.
The inspector general said investigators had identified six F.B.I. employees who did not work in the department’s press office who had contact with the news media, adding that they were referred to the bureau for potential disciplinary action.
The F.B.I. told the inspector general’s office that in response to its previous recommendations, it had enhanced employee training and disciplinary penalties for talking the press.
In a letter to the inspector general, the F.B.I. acknowledged the damage that can be created by leaks.
“The unauthorized disclosure of nonpublic information during an ongoing criminal investigation can potentially impair the investigation, can result in the disclosure of sensitive law enforcement information, and is fundamentally unfair to the subject or target of the investigation,” said Douglas A. Leff, the assistant director for the bureau’s inspection division.