(CNN) The highly anticipated report from the Justice Department's inspector general is expected to yield an unvarnished account of multiple missteps by former top officials at the department and FBI for their failure to follow long-standing protocols in the handling of the Hillary Clinton email probe, according to sources familiar with the matter.

While sources caution the report is not yet final, and responses from individuals named in the report will be included, the exhaustive review of a momentous period in the department's history is expected to criticize former FBI Director James Comey's handling of the investigation at key junctures for violating departmental norms. Of particular focus are the events leading up to his decision to announce in July 2016, without Justice Department approval, that "no reasonable prosecutor" would recommend charges against Clinton, as well as the decision to tell lawmakers days before the November 2016 election that FBI agents had recovered additional emails possibly relevant to the investigation.

CNN reported that at the time that Comey was advised by the Justice Department that his letter to Congress would run counter to department policy to not comment publicly on investigations close to an election, but he sent it anyway.

Inspector General Michael Horowitz is expected to recommend the department devise further written guidelines that would have addressed some of the actions taken by Comey.

Conservative media outlets, White House officials and President Donald Trump's personal lawyers have all eagerly awaited the report's release for months, taking particular interest in its conclusions about the former FBI director.

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