We talked to legal experts who explained why the FBI didn't urge charges against Clinton - and why some think that was a mistake
Comey described Clinton's email practices as "extremely careless" and noted that there is "evidence of potential violations of the statutes regarding the handling of classified information." Still, Comey said that "no reasonable prosecutor would bring such a case" against Clinton and the Justice Department formally closed the probe Wednesday.
The FBI's decision not to recommend charges seemed to have come down to a question of intent, according to Comey.
"Prosecutors necessarily weigh a number of factors before bringing charges," Comey said at a Tuesday press conference. "There are obvious considerations, like the strength of the evidence, especially regarding intent."
Some legal experts say carelessness doesn't constitute sufficient intent for a prosecutor to bring a case against Clinton.
"There are lots of statutes that deal with the mishandling of classified information, but what they all have in common is that it's intentionally or knowingly reckless, not careless," Nancy Gertner, a Harvard Law School lecturer who specializes in criminal law, told Business Insider. "If carelessness were sufficient, we would have indicted half the government."
Benjamin Wittes, a senior fellow in governance studies at the Brookings Institution, noted on the Lawfare blog that "it's not uncommon for high-ranking officials to treat classification rules with a lack of deference."
Gertner made a similar point.
"It would really expose huge numbers of officials to criminal prosecution if we said that carelessness was enough," she said.
Still, the case against Clinton, who is now the presumptive Democratic nominee for president, is "pretty damaging" and she "should have known better," Wittes wrote.
"For the last several months, people have been asking me what I thought the chances of an indictment were," Wittes wrote. "I have said each time that there is no chance without evidence of bad faith action of some kind. People simply don't get indicted for accidental, non-malicious mishandling of classified material."
For Clinton to be prosecuted, Wittes argued, there would have to be more than just an allegation of her mishandling classified information through her use of a private server for her emails.
Wittes agreed with Comey that Clinton should not be charged.
Other legal experts shared a different opinion.
John Malcolm, the director of the Edwin Meese III Center for Legal and Judicial Studies at the conservative Heritage Foundation, said that while "proving specific intent is a hard thing to do," the Justice Department could prosecute Clinton based on her negligence in handling classified information.
"He certainly laid out a fairly compelling case for gross negligence," Malcolm told Business Insider. "He says no reasonable prosecutor would bring this case, but I'm not sure about that."
Malcolm noted that "there are lots of statutes out there on the books that do not require specific intent."
"They may well have been able to establish gross negligence, and that's what the statute calls for," Malcolm said, referring to a provision of the Espionage Act that stipulates it's illegal to disclose classified information through "gross negligence."
Ben Shapiro, a conservative commentator and Harvard Law school graduate, agreed that Clinton could have been prosecuted for gross negligence.
"They say the crime that she committed requires intent. The statute does not require intent. It requires gross negligence. [Comey] called her 'extremely careless' and then proceeded to describe how she was grossly negligent. So clearly it fulfills the requirements of the statute," he told Business Insider.
Shapiro, moreover, argued that intent was in fact present.
"When he says that there was no intent, the question is intent to do what? The intent he's talking about is basically treason. No one has said that she's a traitor," he said.
"People have said that she intended to put classified material on her server without regard for whether it was going to pose a national security risk. ... I don't know how in the world anyone could possibly claim that it would not cause risk to national security."
Robert Weisberg, the co-director of Stanford's Criminal Justice Center, also said the issue came down to whether exposing the emails could have harmed national security. But he said whether that happened was not so clear.
"The case comes down to that issue of whether she was grossly negligent with regard to the possibility of the injury of national security," Weisberg told Business Insider.
He added: "Presumably they didn't find that there was any particular email ... which had content where anybody looking at that content would say, 'Oh my gosh, that could threaten national security."