Hillary Clinton’s campaign chair on Saturday led a chorus of Democratic party fury over the FBI’s decision to review a new batch of her staff’s emails, which was announced just 11 days before the presidential election in a striking break with law enforcement tradition.

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The Clinton campaign launched an extraordinary criticism of James Comey, the director of the FBI, who faced anger for his dramatic and late intervention in the race, which deviated from FBI protocol. Comey stood accused of betraying the bureau’s political neutrality, and came under growing pressure to make public everything he knows.

The latest twist in a topsy turvy election arrived on Friday afternoon, when Comey said in a letter to Congress the FBI would review whether there was any classified information in new “emails that appear to be pertinent to the investigation”. In a carefully worded letter, the director said he wanted to “supplement my previous testimony” about the original Clinton email investigation, which he told Congress had closed this summer, and said: “The FBI cannot yet assess whether or not this material may be significant.”

On Saturday, Clinton campaign chair John Podesta said: “By providing selective information, he’s allowed partisans to distort and exaggerate in order to inflict maximum political damage and no one can separate what is true from what is not because Comey has not been forthcoming with the facts.

“What little Comey has told us makes it hard to understand why this step was warranted at all.”

It is “entirely possible” that the emails are duplicates of those already studied by the FBI in its earlier investigation into Clinton’s use of a private server while secretary of state, Podesta told reporters on a conference call, adding that Clinton would not be distracted in the final days of the campaign.

In July, the FBI closed that investigation. Comey said at the time that Clinton and her aides had been “extremely careless” but not criminal with their email practices.

“Director Comey was the one who decided to take this unprecedented step,” Podesta said, “we now learn, against the advice of senior justice department officials who told him it was against longstanding department policy of both Democratic and Republican administrations.

“Director Comey was the one that wrote a letter that was light on facts, heavy on innuendo, knowing full well what Republicans in Congress would do with it.

“It’s now up to him, who owes the public answers to the questions that are now on the table, and we’re calling on him to come forward and give those answers to the American public.”

Law enforcement sources speaking anonymously told news outlets the new emails came from devices belonging to Anthony Weiner, the disgraced former congressman and estranged husband of Huma Abedin, one of Clinton’s closest aides. Agents uncovered the emails during an investigation into whether Weiner sent sexually explicit text messages to a teenage girl.



Podesta said Abedin had fully cooperated with the FBI investigation from the start. “She’s been fully cooperative. We of course stand behind her.”



Robby Mook, Clinton’s campaign manager, said: “The more information that comes out, the more overblown this entire situation seems to be. That in turn has raised more questions about director Comey from his colleagues in law enforcement circles, to take this extraordinary step just 11 days out from a presidential election.”

Mook highlighted a “startling” Washington Post report that senior officials in the justice department had warned Comey not to go public but he ignored their advice. He also claimed that, based on anecdotes from the ground, Clinton’s supporters were intensifying their efforts to get out the vote.

“Our volunteers are rallying behind Hillary,” he said. “They know what a fighter she is … They’re as upset and concerned as we are here … This has only increased the momentum that we’re feeling among our activists on the ground.”

A jubilant Donald Trump, meanwhile, seized on a potential lifeline for his faltering campaign – on Friday describing Clinton’s handling of classified information as a scandal “bigger than Watergate”.

With barely disguised anger, Clinton herself demanded the FBI explain itself on Friday. “The American people deserve to get the full and complete facts immediately,” she told reporters in Des Moines, Iowa. “The director himself has said he doesn’t know whether the emails referenced in his letter are significant or not.”

The content of the messages is unknown – and may well remain so beyond election day. “Right now, your guess is as good as mine, and I don’t think that’s good enough,” Clinton said.

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Comey is a Barack Obama appointee who was deputy attorney general for George W Bush. As well as the Washington Post, the New Yorker reported officials speaking on condition of anonymity saying that Comey was warned by the justice department before sending his letter to Congress.

“He is operating independently of the justice department. And he knows it,” one official told the Post. “It violates decades of practice,” another told the New Yorker. “It’s aberrational.”

Matthew Miller, who served at the department under attorney general Eric Holder, told the Guardian: “I think it was an unacceptable breach of years of department of justice practice and precedent.

“The department goes out of its way not to take any action close to an election that could influence the outcome of that election. The FBI’s reputation for independence and integrity is really at the core to their ability to do their job effectively.”

Miller described Comey’s decision to provide an unprecedented televised statement at the end of the Clinton investigation in July as “the original sin here”. The director then felt able to answer questions from Congress in more detail than usual, but this is “by far the most serious breach of all”, Miller added.

The former justice department staffer said J Edgar Hoover, the original and controversial FBI director, had done worse than Comey, “but not even Hoover did anything publicly in the closing day of an election that could be seen as tipping the scales.”

Republicans and Democrats alike expressed bafflement at Comey’s timing and ambiguous letter. Senator Dianne Feinstein, a senior Democrat with a history of support for the security agencies, condemned Comey’s conduct. “The FBI has a history of extreme caution near election day so as not to influence the results,” she said. “Today’s break from that tradition is appalling.”

Charles Grassley, the Republican chairman of the Senate judiciary committee, said Comey’s letter to Congress “was unsolicited and, quite honestly, surprising”. He too said it created more questions than answers.

“Congress and the public deserve more context to properly assess what evidence the FBI has discovered and what it plans to do with it,” Grassley said.

Some analysts speculated that Comey felt caught in a bind: if he waited until after the election, or if the new review leaked through back channels, he would have been accused of a cover-up. In an internal email sent to FBI employees, he said he was concerned about balance: the need to inform Congress and the American people versus the danger of a misleading impression about emails.

“In trying to strike that balance, in a brief letter and in the middle of an election season, there is significant risk of being misunderstood, but I wanted you to hear directly from me about it,” he wrote.

Early voting is under way in 37 states, nearly 17m votes have been cast, and Clinton has a healthy lead in most polls. “I think people a long time ago made up their minds about the emails,” she said at her press conference. “And now they are choosing a president.”

Though his own campaign has been plagued by one scandal after another, Trump has regularly berated Clinton over the emails, and his supporters at rallies frequently chant: “Lock her up! Lock her up!” On Friday he accused Clinton of corruption “on a scale we have never seen before”.



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“We must not let her take her criminal scheme into the oval office,” he told a rally in New Hampshire. “Perhaps, finally, justice will be done.”

On Saturday, campaigning in Colorado, Trump made an about-face from his months of criticising the FBI and justice department. “You have amazing people at the Department of Justice, and you have amazing people at the FBI,” he said. “I’ll bet you, without any knowledge, that there was a revolt in the FBI.”

The FBI began investigating Weiner in September, after a Daily Mail report that a 15-year-old girl had exchanged explicit messages with him. By then, Abedin had already announced a separation from her husband.

Trump himself has been accused by several women of sexual assault or inappropriate conduct. He has argued that Clinton “enabled” her husband’s infidelities, and brought three women who accused the former president of wrongdoing to a presidential debate.