FBI files show that President Obama used a pseudonym to exchange 18 emails with then-Secretary of State Hillary Clinton.

Catherine Herridge reported last night that in order for Clinton, or anyone else, to communicate with the president, the person's number or email address would have to be cleared, or 'whitelisted'.

Obama has maintained, including in a March 2015 CBS interview, that he didn't know Clinton used a private email server until it came out in news reports.

Emails released by WikiLeaks this week showed top Clinton aides scrambling on the issue, with Cheryl Mills telling John Podesta in March 2015, "We need to clean this up. He has emails from her - they do not say state.gov."

But according to Fox News senior judicial analyst, Judge Andrew Napolitano, the president "lied directly and pointedly to the American people" with his statement to CBS News. 

Napolitano said the key question now becomes: why did the president lie about it?

The judge said he believes the president "feared" having to testify if Clinton was indicted and probably thought the issue would eventually "go away."

Napolitano agreed with Steve Doocy that the president likely never imagined FBI agents leaking documents about the investigation into the private server.

"This is happening so close to Election Day. I don't know if it's going to move the needle, but it shows the absence of the rule of law in this administration," said Napolitano. 

He pointed out that this information is coming out because FBI agents are "furious" that Clinton was not prosecuted. 

The judge concluded, "The evidence for indictment and for [Clinton's] prosecution was, remains and continues to be overwhelming."

Watch his full analysis above. 

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