Judge Andrew Napolitano said on Fox Nation's "Liberty File" that the Foreign Intelligence Surveillance Act (FISA) court is an obvious violation of the Constitution.

Former FBI Acting Director Andy McCabe and others went to the FISA court to secure a warrant to spy on ex-Trump campaign aide Carter Page, Napolitano said.

He said the court was the product of the Foreign Intelligence Surveillance Act of 1978.

The law was sponsored by Sen. Edward Kennedy (D-Mass.) in the wake of President Richard Nixon's misuse of the FBI and CIA to surveil political opponents.

Napolitano said the standard for obtaining a warrant requires probable cause of contact or a relationship with a foreign person.

He said that might include the regular telephone contact he has with cousins in Florence, Italy.

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He said that legal standard is less than what the Constitution requires under the 4th Amendment, and is an example of Congress "evading the Constitution."

Napolitano said the FISA Court could therefore be a threat to "personal freedom."

He argued that the warrant to spy on Page helped the intelligence operation "silently morph ... into a criminal investigation without anybody noticing."

"Who could trust a court whose very premise is a violation of the Constitution?" he asked.

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