"Very specific guidance has been given to agencies all across the government, which is specifically that employees in the Obama administration should use their official e-mail accounts when they're conducting official government business," White House Press Secretary Josh Earnest told reporters at a livelier-than-usual press briefing.
In an exchange with ABC News, Earnest would not say whether or not Clinton violated that policy or broke the law by using only her personal account.
"I was not in a position to review Secretary Clinton's personal email. That was the responsibility of Secretary Clinton and her team," Earnest said. "They say that they turned over thousands of pages and thousands of emails ... and that is entirely consistent with the requirements of the Federal Records Act."
Earnest added that he could not say whether the White House was aware that Clinton was not conducting her business on an official email account.
Earnest said he did not know if any other Cabinet secretaries are using only their personal email accounts and referred reporters to the individual agencies.
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