By ERIC TUCKER and CHAD DAY, Associated Press

WASHINGTON (AP) — The Justice Department's watchdog faults former FBI Director James Comey for breaking with protocol in his handling of the Hillary Clinton email investigation, but it says his decisions were not driven by political bias ahead of the 2016 election, according to two people familiar with the findings.

The report from the inspector general also criticizes Comey for not keeping his superiors at the Justice Department, including then-Attorney General Loretta Lynch, properly informed about his handling of the investigation, said the people, who spoke to The Associated Press on condition of anonymity because the report was not yet public.

The report's findings are to be made public later Thursday. They represent the culmination of an 18-month review into one of the most consequential FBI investigations in recent history. Overall, the inspector general found problematic political discussions among FBI personnel but found none of the decisions in the Clinton email case were politically motivated.

"We found no evidence that the conclusions by department prosecutors were affected by bias or other improper considerations, rather we concluded that they were based on the prosecutors' assessment of facts, the law and past department practice," the report said, according the people.

The report has long been expected to criticize the FBI's handling of the Clinton email probe, stepping into a political minefield while examining how a nonpartisan law enforcement agency became entangled in the 2016 presidential race. The IG's criticism of Comey's actions was first reported by Bloomberg.

President Donald Trump is looking to the report to provide a fresh line of attack against Comey and his deputy, Andrew McCabe, as he claims that a politically tainted bureau tried to undermine his campaign and, through the later Russia investigation, his presidency. Trump is certain to try to use the report to validate his firing of Comey last year.

But the report could do more to back Democratic claims that the FBI actually contributed to Trump's victory, most notably by reopening in the final days of the race its investigation into whether Clinton mishandled classified information. That development unfolded as Trump's own campaign — unbeknownst at the time to the American public — also came under FBI investigation for possible coordination with Russia.

Inspector General Michael Horowitz, a former federal prosecutor appointed by President Barack Obama, prepared the report. Supporters from both parties regard him as apolitical. His most significant report before this was the 2012 study of the botched Obama-era gun operation known as Fast and Furious.

The Clinton report will examine key actions by FBI leaders, including Comey's decision to publicly announce in July 2016 his recommendation against criminal charges for Clinton, and his disclosure to Congress days before the election that the investigation was being revived because of newly discovered emails.

An earlier inspector general report criticized McCabe and led to his firing on allegations that he misled internal investigators about his role in a news media disclosure. He denies those charges.

Though Trump has repeatedly lambasted FBI leaders as politically biased against him, the inspector general's report — no matter how critical — was unlikely to endorse that conclusion, especially since some of the actions being examined broke from protocol in ways that may have harmed Clinton.

Comey's news conference in the summer of 2016 disclosing the investigation's conclusion was unusual since charging announcements are normally made by the Justice Department, not the FBI. Cases that end without charges are rarely discussed publicly.

In this instance, Comey said that though the FBI found Clinton and her aides to be "extremely careless" in handling classified material, "no reasonable prosecutor" could have brought a case against her.

The watchdog report being released Tuesday said Comey was not motivated by bias at the news conference.

"We found no evidence that Comey's public statement announcing the FBI's decision to close the investigation was a result of bias or an effort to influence the election," the report says.

At a congressional hearing last May, he said he was concerned that the Justice Department could not "credibly" announce the conclusion of its investigation, in part because Lynch had met aboard her plane with former President Bill Clinton.

Lynch described that meeting as a chance encounter unrelated to the case, but Clinton's critics seized on it to question Lynch's objectivity.

Also investigated by the IG was Comey's decision, against the recommendation of the Justice Department, to reveal to Congress that the FBI was reopening the email investigation following the discovery of additional messages. The FBI obtained a warrant nine days before the presidential election to review those emails, found on the laptop of former Rep. Anthony Weiner, but ultimately determined there was nothing in them that changed its original conclusion.

Officials from Justice and FBI are expected to testify about the report before congressional committees next week, including the House Judiciary Committee, which has been doing its own investigation into the Clinton probe.

Also Thursday, The AP obtained a document listing preliminary conclusions of that GOP-led investigation, which has been conducted jointly with the House Oversight and Government Reform Committee.

The document says the Republicans on the committee have "substantial questions about whether DOJ and FBI properly analyzed and interpreted the law surrounding mishandling of classified information."

The partisan investigation charges that the FBI did not follow legal precedent and treated the Clinton probe differently from other

Associated Press writer Mary Clare Jalonick contributed to this report.