Fox News chief White House correspondent John Roberts reported that White House Press Secretary Sean Spicer recently conducted a phone check of staffers to determine if anyone has been leaking confidential information to the press.

Spicer asked a group of about 10 people to lay whatever phones they had with them on the table and checked to see if the phones had apps which erase messages after being viewed such as Confide and Signal, a senior administration official told Roberts.

Spicer also looked for evidence to see if a few specific phone numbers had been called, according to Roberts.

Fox News senior judicial analyst Judge Andrew Napolitano joined "Fox & Friends" Monday, saying that although Spicer's phone check was "very dramatic," he needs to have a team he can trust.

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The judge said there are two types of leaks that could potentially be occurring: members of the intelligence community revealing what they know in order to manipulate the president or someone in the White House telling a friend in the press information that the president does not want disclosed.

"I don't blame Donald Trump. He is rightfully angry about this stuff going on," said Napolitano, adding that the president's own staff leaking information "fundamentally undermines the way he wants to run the government."

The judge said he believes White House staffers were required to sign an agreement saying they would not leak any information to the press. Violating such an agreements would be grounds for disciplinary actions.

Watch the interview with Napolitano above. Plus, see what Spicer told Judge Jeanine Pirro regarding "ridiculous" reports that the White House excluded certain news organizations from a recent press gaggle.

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