James Comey has absolved Hillary Clinton of any criminal wrongdoing in regard to a late-found trove of her emails, but his belated exoneration of the Democratic presidential nominee will most likely be as controversial as his unseemly intervention, when just 11 days remained in a bitterly contested campaign.
With little more than 24 hours to the polls opening, FBI chief"Based on our review, we have not changed our conclusion that we expressed in July with respect to Secretary Clinton," Comey said in a letter to congressional committee chiefs on Sunday.
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FBI clears Clinton over emails...again
Hillary Clinton will not face any charges after the FBI revisited her use of emails, FBI director James Comey has told US Congress.
The letter will be welcomed by the Clinton campaign, which saw its winning polls lead evaporate after the October 28 bombshell when Comey wrote to Congress, revealing the existence of a batch of emails that might "be pertinent" to an earlier investigation that had cleared Clinton and her senior staff of wrongfully transmitting classified material through her controversial private email server.
Clinton had a new spring in her step as she alighted from her aircraft for a rally in Cleveland, Ohio, although Comey's announcement will have done little to douse Democratic fires of contempt for him.
And it engulfed the Trump campaign in renewed paroxysms of anger and disbelief, abruptly ending 24 hours of nonsense in which key Trump surrogates were hailing Trump's response to an attempted assassination that wasn't, as proof that he was presidential material.
Seemingly wasting time, campaigning in Minnesota which no Republican candidate has carried since 1972, Trump declared: "She's the most corrupt person ever to seek the presidency of the US. Clinton will be under investigation for a long time for the many crimes against her. It's a rigged system and she's protected," he said.
This new Comey letter will be the basis for renewed attacks by the Trump campaign, which used the FBI's reopening of the email investigation to great effect, hammering "crooked Hillary" and super-charging the "lock her up" demands of Trump's rallies.
As always is the case with Trump on the hustings, truth was irrelevant, facts not needed - he just made it up. The FBI had found the missing 33,000 emails; that all 650,000 emails in the Abedin-Weiner laptop were Clinton-related; that Clinton had committed perjury; that because the FBI had reopened the case, there had to have been "a most egregious criminal offence".
And were his audiences not hearing this nonsense in the news?
"Wow, Twitter, Google and Facebook are burying the FBI criminal investigation of Clinton. Very dishonest media," Trump tweeted on October 30.
After months of slamming Comey and the FBI as key players in a conspiracy to rig the election against him because they did not charge Clinton the first time around, in the past week Trump had been hailing Comey as a heroic, even courageous figure.
But late on Sunday, it seemed the FBI chief had been relegated once again, as Trump declared that Clinton was "protected by a rigged system".
A likely point of attack for Trump and his surrogates will be the speed at which FBI agents, who Comey says were "working around the clock", processed the reported 650,000 emails found on a laptop used by Clinton aid Huma Abedin and her estranged husband Anthony Weiner, a disgraced former congressman who was being investigated for his internet-based sexual relationships with women, including one who was 15 years old.
An early response from the Trump campaign was this tweet from key surrogate Newt Gingrich: "Comey must be under enormous political pressure to cave like this and announce something he can't possibly know."
The advantage for Trump and congressional Republicans, who are driven by a visceral hatred of the Clintons, is that the genie unleashed by Comey doesn't easily fit back in its bottle.
As Trump's campaign manager Kellyanne Conway told MSNBC on Thursday: "Well, the damage is done to Hillary Clinton, that no matter how it's being termed, the voters are hearing it for what it is - a culture of corruption."
Millions of early votes were being cast while renewed doubt hung over Clinton - not just for the presidency, but also for down-the-ticket seats in the House and the Senate, which are impacted by voter attitudes to the presidential candidate.
More importantly, Republicans seemed to acknowledge an analytical consensus that the underlying fundamentals in opinion polls still pointed to a Clinton victory, with strident warnings that, as president, Clinton would get no honeymoon and would become the focus of relentless congressional committee investigations and more gridlock in Congress.
The tenor of a bitterly personal and hate-filled campaign had already raised questions of the legitimacy and mandate in a Clinton victory. And Comey's exoneration of Clinton on Sunday will most likely increase, not reduce, Republican anger.
Comey is in the early stages of a 10-year tenure as FBI chief. But he has been under intense criticism, in Congress, in the FBI and in the media for his bizarre behaviour - effectively bombing Clinton from the water by revealing that she was under investigation, but not revealing that Trump, too, was being investigated for his, and several of his senior aides', alleged links to Russia.
The whole affair suggests that the FBI has been co-opted for partisan political purposes by the Trump campaign.
It has brought to light near civil war within the agency that Comey apparently cannot control. His tenured position is protected, but it's highly likely that, whoever is the next president, there will be demands for his resignation - if not from the White House, then from congressional and other surrogates.
And the record shows that perhaps Comey should offer his resignation before anyone asks for it. The reality and the optics of the past week have focused attention on the ugliness of the agency's almost 40 years under J. Edgar Hoover, its efforts to destroy the legend of Martin Luther King jnr, eavesdropping on a dozen justices of the Supreme Court, and monitoring serial protest and activist movements, as early as the Vietnam War, and, more recently, the Black Lives Matter movement.
Comey and his agency are politically damaged goods. For much of his adult life he has been a registered Republican voter and the double standard in his handling of political investigations in the course of this campaign appears overtly partisan: tell the world his guys were digging into Clinton, but stay mum on their probe of Trump's Russian connections.
And while other US security agencies put their name to a statement of belief that Russia was attempting to manipulate the outcome of the election, by hacking the Democrats' computers, why did he insist that the FBI's name be removed from the list?
Further, if, as his media surrogates argue, he made his October 28 statement to Congress to pre-empt leaks from within his own organisation, why did he not warn his agents of their statutory obligation not to leak when he tried to explain his own conduct in an agency-wide email on the same date?
And why did he appear to mislead Congress in his first letter when, by stating "the investigative team briefed me on this yesterday", Comey implied that "yesterday" was when he first heard of it?
But subsequent reports indicated he had been aware of the existence of the new emails for some weeks, a timeline that seemed to be confirmed by Trump surrogate Rudy Giuliani's televised response when the story broke: "I thought it was going to be three or four weeks ago."
What followed was a flood of leaks, all inflicting further damage on Clinton. All of which were picked up by the Trump campaign, which persisted in peddling the most damaging, such as a Fox News report that indictments were likely to spring from an FBI investigation of the Clinton family foundation – even when the reporter involved had gone on air to withdraw and to apologise for a story that had no basis in fact.
The volume of the internal leaks, many of them carried to the media and to the Trump campaign by activist former agency officers, shrieked of an agency in which elements have gone rogue – seemingly taking Comey's breach of protocol in advising Congress of the new Clinton investigation as a green light for their own trampling of protocols that insist on public silence about the agency's work.
Giuliani gleefully told Fox in advance of Comey's October 28 letter that there was "a surprise or two that you're going to hear about in the next few days". And in its immediate aftermath, he couldn't help himself, going back on air to declare: "Did I hear about it? You're darned right I heard about it."
Insiders talked of hostility to Clinton, particularly in the FBI's New York field office, where a group of rogue officers was persevering with trying to build a new corruption case against the Clinton family foundation, apparently based on some media reports and – wait for it – the contents a book called Clinton Cash, published by the Alt-Right media empire presided over by Steve Bannon, who now serves as Trump's campaign chief.
Rejection of their work by the public integrity prosecutors was read as politically motivated protection for the Clintons, and this could be a reflection of the FBI's "Trumpland" demographics – predominantly white, with very few women, African-American or Latino staff.
The agency's demographic breakdown is a threat from within that Comey prefers to refer to merely as "a crisis".
In a speech in July 2016, he said: "We have a crisis in the FBI and it is this: slowly but steadily over the last decade or more, the percentage of special agents in the FBI who are white has been growing ... We are now 83 per cent white in our special agent cadre.
"I've got nothing against white people - especially tall, awkward, male white people - but that is a crisis for reasons that you get and that I've worked very hard to make sure the entire FBI understands. That is a path to fall down a flight of stairs."
His numbers are rising, but so slowly - African-American agents are up from 581 in March to 603 in August – but are still less than the 652 African American agents the bureau had four years earlier. Ditto Latinos – up from 882 to 888, but less than the 938 Latino agents in 2012.
"I will have failed if I don't change this," Comey said.
The director's allies argued following his October 28 letter that he was motivated by a need to protect his own reputation and that of his agency.
In the wake of their several roles in the last raucous week of a raucous campaign, that might be mission impossible.
After all, FBI agents are sworn to "protect and serve" all Americans.