The inspector general concluded that the FBI director, who announced in the summer of 2016 that Clinton had been "extremely careless" with classified material but would not be charged with any crime, departed from normal Justice Department protocol numerous times.
But it also said, "We found no evidence that the conclusions by the prosecutors were affected by bias or other improper considerations; rather, we determined that they were based on the prosecutors' assessment of the facts, the law and past department practice."
The conclusions were contained in a 500-page report that documents in painstaking detail one of the most consequential investigations in modern FBI history and reveals how the bureau, which for decades has endeavored to stand apart from politics, came to be entangled in the 2016 presidential election.
Trump supporters quickly focused on the report's recounting of anti-Trump text messages from two FBI officials who worked the Clinton probe and later the Russia case, including one in which an agent says, "We'll stop it" with regard to a possible Trump victory.
The report suggests that text from Peter Strzok, who was later dropped from Mueller's team, "implies a willingness to take official action to impact the presidential candidate's electoral prospects."
Spokeswoman Sarah Huckabee Sanders said the report "reaffirmed the president's suspicions about Comey's conduct and the political bias amongst some of the members of the FBI."
But the report rejects the Trump talking point that the FBI favoured Clinton over him and that its leaders were driven by politics. It also does not second-guess the FBI's conclusion that Clinton should not have been prosecuted, despite repeated assertions by Trump and his supporters that anyone less politically connected would have been charged.
The report underscores efforts by senior FBI and Justice Department leaders in the final stages of the presidential race to juggle developments in the Clinton investigation — she had used private email for some government business while secretary of state — with a separate probe into potential coordination between the Trump campaign and Russia that was diverting FBI resources and attention. The Russia investigation was unknown at the time to the American public.
The FBI, in a statement accompanying the report, accepted the conclusion that Comey broke from protocol and that errors in judgment by staff damaged the bureau's reputation.
Comey wrote an opinion piece for The New York Times in which he said he disagreed with some conclusions but respected the watchdog's work.
Trump is certain to use the report's harsh assessment of FBI actions to try to validate his firing of Comey last year, an act central to special counsel Robert Mueller's investigation into whether the president sought to obstruct justice.
The White House cited as the original rationale for Comey's firing his handling of the Clinton investigation, even though Trump days later said he was thinking of "this Russia thing."
On the other side, even absent political bias, the report alleges a long series of misjudgments that Democrats will likely use to support their belief that Clinton was wronged by the FBI.
The watchdog faults Comey for his unusual July 5, 2016, news conference at which he disclosed his recommendation against bringing charges in the email investigation. Cases that end without charges are rarely discussed publicly.
And Comey did not reveal to Attorney General Loretta Lynch his plans to make an announcement.
"We found that it was extraordinary and insubordinate for Comey to do so, and we found none of his reasons to be a persuasive basis for deviating from well-established Department policies in a way intentionally designed to avoid supervision by department leadership over his actions," the report says.
Comey has said he was concerned that the Justice Department itself could not credibly announce the conclusion of its investigation, in part because Lynch had met earlier in the summer aboard her plane with former President Bill Clinton. Both said they did not discuss Hillary Clinton's case.
Concerned about the "appearance that former President Clinton was influencing" the probe, Lynch began talking to her staff the next morning about possibly recusing herself from overseeing the investigation, according to the report.
She told the inspector general she decided not to step aside because it might "create a misimpression" that she and the former president had discussed inappropriate things.
Bill Clinton, who was also interviewed in the IG investigation, said he had "absolutely not" discussed the email probe.
Also criticised was Comey's decision, against the recommendation of the Justice Department, to reveal to Congress that the FBI was reopening the investigation following the discovery of new emails.
The FBI obtained a warrant nine days before the presidential election to review those emails, found on the laptop of former Rep. Anthony Weiner, and ultimately determined there was nothing in them that changed its original conclusion.
The report faulted the FBI for failing to act with more urgency in reviewing emails from Weiner's laptop. Comey has said had he had known more about the laptop earlier, it might have affected his decision to notify Congress.
The report sharply criticises FBI agent Strzok and a now-retired FBI lawyer Lisa Page for text exchanges that it says were "deeply troubling" and created the appearance "that investigative decisions were impacted by bias or improper considerations."
Most of the problematic texts relate to the FBI's Russia investigation, the report notes.
Both Strzok and Page acknowledged that some of their texts could be read as showing bias against Trump, but both insisted bias played no part in their work.
- AP
