Former FBI Director James Comey "deviated" from official procedures in how he handled the agency's investigation into Hillary Clinton, and consequentially hurt the organization's reputation, the Justice Department inspector general concluded in its report to be released Thursday.

"While we did not find that these decisions were the result of political bias on Comey’s part, we nevertheless concluded that by departing so clearly and dramatically from FBI and department norms, the decisions negatively impacted the perception of the FBI and the department as fair administrators of justice,” Inspector General Michael Horowitz wrote, according to Bloomberg, which obtained the conclusions of the report hours before it is set to go public.

Comey oversaw the probe into Clinton's use of a private email server during her four years as secretary of state.

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In October 2016, months after closing the investigation and recommending no charges, Comey informed lawmakers that the FBI reopened it just two weeks before the presidential election, and said he made the decision to do so as a result of information found on a laptop that belonged to Anthony Weiner, the ex-husband of Clinton aide Huma Abedin.

The case was closed again, with no new conclusions, only a few days before the election, which Clinton lost.

Horowitz examined the October 2016 incident as well as Comey's July 2016 announcement that he did not believe a prosecutor had reason to file criminal charges against Clinton for how she sent and received classified information on her home server.

Horowitz concluded there was a “troubling lack of any direct, substantive communication” between Comey and then-Attorney General Loretta Lynch before he publicly stated he did not believe she should try to bring a case against Clinton.

“We found it extraordinary that, in advance of two such consequential decisions, the FBI director decided that the best course of conduct was to not speak directly and substantively with the attorney general about how best to navigate those decisions," Horowitz wrote.

Lynch backed Comey's decision, but her role in the process was called into question after she secretly met with former President Bill Clinton on an airport tarmac during the probe. Both parties insisted afterward that they did not talk about the investigation into the former president's wife.

The inspector general also concluded text messages showing that FBI agents Peter Strzok and Lisa Page opposed Trump did not have an effect on the investigation. Both of those agents worked on Special Counsel Robert Mueller's probe into Trump's relationship with Russia during the 2016 election.

“We did not find documentary or testimonial evidence that improper considerations, including political bias, directly affected the specific investigative actions we reviewed,” Horowitz added. “The conduct by these employees cast a cloud over the entire FBI investigation.”