Marc Thiessen reacted to Hillary Clinton's latest defense of her use of a private email server by paraphrasing Ronald Reagan: "There she goes again."

Thiessen said Clinton came up with "yet another new email excuse." He then ran through Clinton's explanations for using a private server over the past year.

"Now she comes up with a new excuse - there was nothing with a Classified header, that all classified information has a header."

Thiessen said that first of all, that's not true and Clinton is required to protect all classified information, marked or unmarked.

"But second, if there were classified information on her server without any headers, how did it get there? The way it got there was that she and her staff took the headers off. Classified information can't just appear; it has to be entered in. The two systems, the classified email system and the [unclassified], are not connected."

Therefore, Thiessen said, Clinton or someone on her staff put classified information onto an email without a header, which is a violation of the law.

"And she's using that as a defense. It's unbelievable."

Watch the full segment above.

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