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Judge Andrew Napolitano believes the FBI must have found something "substantial" in newly-uncovered emails to cause the bureau to reopen its investigation into Hillary Clinton's private email server.

Judge Napolitano said the fact that FBI Director James Comey sent a letter to the chairs of congressional intelligence and judiciary committees suggests that it "probably does involve national security."

"And when FBI agents looked at it, they did not know for sure if it was classified or not, and they need to confer with their colleagues in the intelligence community in order to make that determination," Judge Napolitano explained.

He said that it's possible that the new information could be evidence that top Clinton aide Huma Abedin was not truthful in her interview with the bureau or it could be something that was deleted from Clinton's servers that investigators had not seen before.

Get more insight from the judge above, and let us know what you think in the comments.

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