(CNN) -- The Justice Department's inspector general will issue a report on how top federal officials handled the investigation into Hillary Clinton's use of a private email server while secretary of state.
Here are the key dates of the investigation from 2015 and 2016:
July 10, 2015 -- The FBI opened a criminal investigation, code-named "Midyear Exam," into Hillary Clinton's handling of classified information while secretary of state.
Late September 2015 -- As then-FBI Director James Comey prepared for his first public questions about the case at congressional hearings and meetings with reporters, he met with then-Attorney General Loretta Lynch at the Justice Department. Lynch asked him to refer to the investigation as a "matter," Comey said in his book, "A Higher Loyalty."
In a statement to CNN after Comey's book was released, Lynch defended her language and said no concerns were raised. "If he had any concerns regarding the email investigation, classified or not, he had ample opportunities to raise them with me both privately and in meetings. He never did," Lynch said.
June 27, 2016 -- Lynch met with President Bill Clinton at an airport in Phoenix after Clinton realized the two were on separate planes on the same tarmac.
July 1, 2016 -- Lynch said at the Aspen Institute that she "wouldn't do it again"; she made clear she wouldn't formally recuse herself from the investigation, but would accept the recommendations of career DOJ staff and the FBI.
July 2, 2016 -- Hillary Clinton was interviewed by FBI for three-and-a-half hours.
Morning of July 5, 2016 -- Comey, in "A Higher Loyalty," said he called Lynch and Deputy Attorney General Sally Yates and told them that he planned to hold a news conference on the Clinton case and was not coordinating the statement with the Justice Department. Comey writes in the book Lynch asked only, "What will you be recommending?" and he replied with, "I'm sorry, but I'm not going to answer that." He added: "It's very important that I not have coordinated this in any way with the department. I hope some day you will understand why." Lynch said nothing, according to Comey.
Later on July 5, 2016 -- Comey issued a surprise statement on the email server investigation recommending no charges against Clinton; he said DOJ officials "do not know what I am about to say."
September 22, 2016 -- CNN reported federal prosecutors were investigating former Rep. Anthony Weiner, the husband of top Clinton aide Huma Abedin, for sexting with a minor.
September 28, 2016 -- Comey testified in front of the House Judiciary Committee.
Asked if he would reopen the Clinton case if he found new information, Comey said: "It's hard for me to answer in the abstract. We would certainly look at any new and substantial information."
On or about September 28, 2016 -- FBI Deputy Director Andrew McCabe was informed about Clinton emails found on Weiner's laptop. "Got called up to Andy's earlier...hundreds of thousands of emails turned over by Weiner's atty to sdny, includes a ton of material from spouse. Sending team up tomorrow to review ... this will never end ...," FBI counterintelligence agent Peter Strzok wrote to FBI lawyer Lisa Page. The two worked closely on the Clinton email probe, and later on the FBI's investigation into Russian meddling in the election.
Early October 2016 -- Comey, in "A Higher Loyalty," wrote that someone at FBI (he believes McCabe), mentioned to him that the Weiner had a laptop might have some connection to the Clinton case. "I don't remember the conversation clearly. I suspect that is because it seemed like a passing comment and the notion that Anthony Weiner's computer might connect to Midyear and Hillary Clinton made no sense to me," Comey said.
October 24, 2016 -- The Wall Street Journal reported that Jill McCabe, the wife of Andrew McCabe, accepted nearly $500,000 from the political action committee of then-Democratic Virginia Gov. Terry McAuliffe, a Clinton family ally, during a failed bid for state senate in 2015.
October 26, 2016 -- Rudy Giuliani went on Fox News to say that then-Republican presidential nominee Donald Trump had "a surprise or two that you're going to hear about in the next two days."
October 27, 2016 -- Comey held a meeting with the Clinton e-mail investigation team at the FBI to discuss obtaining a search warrant for a set of Clinton-related emails the FBI had discovered on Weiner's laptop.
Comey wrote in his memoir that the FBI agents in the room told him that it "would take many weeks" to review the newly discovered emails, and that there was "no chance" that it would be done before the election.
October 28, 2016 -- Comey wrote to Congress saying, "In connection with an unrelated case, the FBI has learned of the existence of emails that appear to be pertinent to the investigation." Lynch and Yates privately said the letter ran afoul of DOJ policy.
October 30, 2016 -- Prosecutors obtained a search warrant to begin reviewing Weiner's laptop for emails related to the Clinton investigation.
November 1, 2016 -- McCabe sent emails to FBI executives and officials overseeing the Clinton email Investigation informing them that he was recusing himself from those investigations.
November 2, 2016 -- Email is leaked showing that Peter Kadzik, then-head of legislative affairs at the Justice Department, offered Clinton campaign chairman John Podesta a "heads-up'" in May 2015 about a congressional hearing where a Justice official was likely to be questioned about Clinton's email use.
November 6, 2016 -- A second Comey letter to Congress stated, "Based on our review, we have not changed our conclusions that we expressed in July." CNN reported that DOJ agreed with decision to send letter.
November 8, 2016 -- Donald Trump is elected President of the United States.
CNN's Marshall Cohen contributed to this report.
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