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Donald Trump has leapt on fresh revelations in Hillary Clinton's email scandal, doubling down on his claim the drama is "worse than Watergate".
News the FBI is investigating a new set of emails, found on a laptop used by one of the Democratic nominee's top aides, has thrown a grenade into her camp before the final week of campaigning.
With scant detail released on the emails' significance, political commentators and campaigners are in overdrive speculating on their contents and making wild accusations.
Trump's people say Clinton is unfit to be president. Clinton's team have turned on Bureau chief James Comey, saying his decision to publicise the discovery without more information so close to the election violates his duty to remain bipartisan.
Meanwhile, CNN contributor Donna Brazile resigned after separate emails she sent to Clinton's chairman were released by Wikileaks, showing she passed the candidate information on questions ahead of a debate and town hall meeting.
It's hardly "cutting through the noise" of the campaign, something the Democratic candidate had hoped to achieve in the run-up to polling day.
Here's why the emails are important and what they mean in terms of trust for the potential future president.
None of the new emails were to or from Clinton, a law enforcement official told Newsweek, and there is no indication she withheld them during the investigation into her use of email as Secretary of State.
The FBI found the 650,000 messages on a laptop seized as part of an investigation into disgraced Congressman Anthony Weiner sexting a 15-year-old girl.
Weiner is the estranged husband of Clinton's gatekeeper and "second daughter" Huma Abedin, who apparently used the computer to print out emails for her boss to read.
Comey revealed the discovery in a letter on Friday, after the Bureau said in July it had completed its investigation into Clinton's use of a private server to handle official emails.
If any of the documents found on the laptop were classified, Abedin could be judged to have mishandled them, but she will only have committed a crime if it can be shown she intended to disclose the contents or knew she was mishandling the information.
THE OLD EMAILS
Republican presidential candidate Donald Trump has been using the latest revelations to his advantage as the campaign enters its final week. Photo / AP
The original investigation was completed in July after none of the emails found on Clinton's private server in the basement of her home were found to have compromised state security.
Classified government documents typically aren't shared by email but discussed in enclosed areas known as SCIFS (Sensitive Compartmented Information Facilities), sent via courier or through other secure forms of communication.
But the scandal still leaves a bad taste in the mouth.
Timothy Naftali, founding director of the Richard Nixon Presidential Museum, told the New York Times the State Department under Clinton appeared too well run for incompetence to be the sole reason for the email bungle, and "the public deserves a better explanation."
Clinton had the authority to determine the classification of most of her own communication but not that of the CIA, White House or other agencies who could have emailed her.
Instead of allowing State Department archivists to review her email, she kept it all and returned only what her representatives decided was official.
Perhaps she didn't trust civil servants to maintain her privacy, suggests Associate Professor Naftali, but her actions risked the jobs of staff close to her who may have known what she was doing.
Five individuals were eventually granted immunity by the Justice Department.
'DARKEST MOMENT IN FBI HISTORY'
Photo / AP
Unless the FBI finds evidence Clinton deliberately tried to expose the American public, the scandal is unlikely to result in any criminal conviction.
But while state security may not have been exposed, and emailgate may not be Watergate, it doesn't paint the Democratic nominee in the best light.
Her biggest problem in this campaign has been that many voters see her as untrustworthy, part of an elite ruling dynasty and someone who doesn't think the rules apply to them.
Clinton's use of a private email server for official emails suggests an arrogance and lack of caution - something she was also accused of in relation to meetings with top Clinton Foundation donors when she was Secretary of State.
Even if her actions weren't malicious or ethically compromised, it is up to a president to behave in a way that is demonstrably unimpeachable.
The fact her lead over Trump has narrowed in the wake of the latest revelations shows the public wants reassurance.
If Trump now wins, Democrats will say the election result was unfair on the basis of Comey's revelations. If Clinton wins, Republicans have already said they will insist on further investigation into why the email scandal wasn't further explored by the FBI.
It could go down in history as one of "thedarkest moments in the bureau's history", according to Newsweek.
Not only has a supposedly impartial institution been dragged into this nasty election campaign, but America's future leadership looks doomed.
