Hillary Clinton’s FBI investigation is reportedly reaching its final stages, with the presumptive Democratic nominee soon talking to investigators, and the decision on whether to recommend indictment coming not long afterward.

But, as the investigation continues, Clinton is already under fierce attacks for her alleged use of a private email server to share classified information with Republican opponents saying she jeopardized national security and showed she is not fit to serve as president.

Investigators have already spoken to several close aides of Clinton, and are reportedly planning to interview Clinton sometime in the coming days or weeks.

“This certainly sends the signal that they are nearing an end to their investigation,” Steven Levin, a former federal prosecutor and current partner at the law firm Levin & Curlett, told The Hill.

Levin said the fact that Clinton’s interview will be the final piece of the investigation means she is the focus, even though the FBI has declined to say if it is centered on Clinton specifically.

“Typically, the way we structure investigations when I was a federal prosecutor is that we would seek to interview the target last,” he said.

“As you begin to interview people who are extremely close to the target of an investigation — people who are considered confidantes … you typically interview those people towards the final stages of the investigation,” he added. “So that way if they tell you something that is contrary to something you’ve already learned, you can immediately challenge them on that information.”

Matthew Whitaker, a former U.S. attorney who heads up the Foundation for Accountability and Civic Trust, told The Hill that there is a lot at stake with Clinton’s interview, as she will be grilled by investigators and could be in trouble if her answers don’t match the ones they already have from other interviews.

There are still some outstanding questions about the investigation, including whether Hillary Clinton intentionally shared classified documents, which some believe is necessary for criminal charges to be levied. But national security expert Bradley Moss told The Hill that doesn’t matter.

“All that matters for strict legal purposes of culpability is whether the person, by virtue of their official position, came into possession of classified information and affirmatively removed the information to an unauthorized location (i.e., the private server),” he said. “Whether the person knew or suspected the information was classified is irrelevant.”

There are also questions about when the FBI investigation may come to an end. Though most experts agree that it is entering the final stages, just how long that could take is up for interpretation. Some believe the FBI is under pressure to release its findings and possibly recommend indictment before the Democratic National Convention this summer, but FBI director James Comey has said there is no such timeline.

.@LillyLoverly How about the fact that it's a security probe not a criminal investigation? https://t.co/6VKiPsUQai @RBReich — Bobby Cole (@skeptibeard) May 3, 2016

Republican Congressman Darrell Issa, who once served as chair of the House Government Oversight Committee, said he believes it will not be concluded until after the November election, the Washington Examiner reported.

Hillary Clinton FBI Indictment Could Come After Clinton Given The Nomination https://t.co/wlRLL5VjDk #FeelTheBern — QuaiaVoice (@QuaiaVoice) May 4, 2016

If Clinton were indicted before the November election, but after she officially becomes the Democratic Party’s candidate, it could create a difficult decision for the party on whether to remove Clinton, who could be facing misdemeanor charges depending on the findings, or replace her with another candidate.

Whenever it may finish, the FBI investigation has already become a major point of attack for opponents of Hillary Clinton. Republican National Committee Chairman Reince Priebus on Friday slammed the presumptive Democratic nominee, saying her “reckless attempt to skirt government transparency laws with her secret email server jeopardized our national security.” Priebus added that Clinton lacks the “judgment and character to be president.”

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