Judge Andrew Napolitano said that the use of intelligence data for political purposes would be the "the most serious threat to personal liberty in America" since the Civil War.

The House Intelligence Committee subpoenaed the Central Intelligence Agency, Federal Bureau of Investigation, and National Security Agency Wednesday for documents related to suspicions that Obama officials unlawfully unmasked the names of Americans associated with then-candidate Trump during the presidential campaign.

Chairman Devin Nunes named three former Obama administration officials suspected of illegal unmasking: Susan Rice, John Brennan, and Samantha Power.

The judge said "the use of raw intelligence data for political purposes" will destroy our freedoms and is a threat to the nation's stability. 

"Mass suspicionless spying" is unconstitutional, he stressed.

Napolitano stated he believes the spying was a last-ditch attempt by the Obama administration to thwart Donald Trump being elected to the White House, adding that it may have gone beyond Michael Flynn. 

The judge argued that Democrats would have a different stance on the issue if it emerged that someone in their own party was subjected to the unmasking.

Watch the segment above.

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