The emails Comey was referring to in his October 28 notification he sent to Congress were found on former New York Rep. Anthony Weiner's laptop - former Clinton State Department aide Huma Abedin's estranged husband.
Clinton said on Tuesday her election bid was derailed in part by Comey's announcement about the renewed probe of her use of a private email server while she was secretary of state.
"To not speak about it would require an act of concealment in my view", Comey said. "Concealing in my view would be catastrophic".
Just days later, Comey concluded the emails were mostly personal or duplicates of what the government had already examined prior to clearing Clinton of any criminal charges.
Dianne Feinstein (D-Calif.) asked Comey about the FBI reopening their investigation into Clinton's email scandal and the "public letter" informing Congress about the information.
Comey says it made him - in his words - "mildly nauseous" to think he might've had an influence on the 2016 election, as many Democrats believe.
"You may think we're idiots, but we're honest people", FBI Director James Comey said.
Comey mostly refused to comment on the FBI's ongoing investigation involving potential Russian connections to Trump's 2016 campaign and its meddling in the election overall.More news: Philadelphia takes home top prizes at the 2017 James Beard Awards
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The FBI launched a counter-intelligence investigation into Russian Federation and the Trump campaign in July, but did not confirm the probe until March.
Comey's testimony, which also drew strong reactions from Democrats, is the first time the Federal Bureau of Investigation director has shed some light into the moments leading up to the 2016 presidential election, a topic of debate that still resonates with Americans and the two people at the center of the story: Clinton and President Donald Trump.
"FBI Director Comey was the best thing that ever happened to Hillary Clinton in that he gave her a free pass for many bad deeds!"
Some Republicans defended Comey's actions and pressed him about what evidence underpins accusations of the Trump campaign contacts with Russian Federation. "We have to ask ourselves what is the right thing to do and then do it".
Speaking on Capitol Hill today, Comey said that if he could revisit his actions from the fall, he would have made the same decisions. I'm not trying to talk you into this, but I want you to know my thinking. At the time, Weiner and Abedin were married. "Lordy, that would be really bad", Comey said.
The Clinton email issue was blown wildly out of proportion by the media and Republicans, who pretended that nearly every Republican running for office who had been an executive didn't also have a private email or stolen government computer scandal, and that the inadvertent mishandling of classified information is generally not treated as a criminal matter. "I am very aware of the challenges, the problems, the shortfalls that we had", Clinton said. He said that the FBI does not expect to divulge anything about the Russian Federation investigation until it is completed.
Under questioning from California Democratic Sen.