National Security Council aide Lt. Col. Alexander Vindman is sworn in to testify before the House Intelligence Committee on Capitol Hill in Washington, Tuesday, Nov. 19, 2019, during a public impeachment hearing of President Donald Trump\'s efforts to tie US aid for Ukraine to investigations of his political opponents. Andrew Harnik/AP

An attorney for Lt. Col. Alexander Vindman, a key impeachment witness and decorated US Army officer, has demanded that Fox News retract a suggestion made on the network groundlessly alleging that he is a Ukrainian spy.

„As a result, LTC Vindman and his family have been forced to examine options, including potentially moving onto a military base, in order to ensure their physical security in the face of threats rooted in the falsehood that Fox News originated,“ attorney David Pressman wrote in a letter to Fox.

Vindman has come under attack from Republican media, activists, and President Donald Trump himself for describing his concern after hearing Trump pressure Ukraine’s president to investigate a domestic rival in a July 25 call.

Vindman was born in Ukraine, but moved to the US with his family when he was three-years-old.

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An attorney for Lt. Col. Alexander Vindman, a key witness in the impeachment probe, has demanded that Fox News retract a groundless claim made on the network that the decorated Iraq war veteran is a foreign spy.

The complaint centers on a discussion that took place on „The Ingraham Angle“ on October 28, in which host Laura Ingraham discussed Vindman’s closed-door testimony to the House that day with John Yoo, a law professor who served in the administration of President George W Bush.

Here’s the exchange that’s the center of the complaint, in which Ingraham referred to a New York Times report claiming Ukrainian officials sought advice from Vindman on how to deal with Rudy Giuliani, Trump’s personal attorney.

Ingraham: „Here we have a US national security official who is advising Ukraine, while working inside the White House, apparently against the president’s interest, and usually, they spoke in English. Isn’t that kind of an interesting angle on this story?“

Yoo: „I found that astounding. Some people might call that espionage.“

Part of Vindman’s role on the National Security Council would be to liaise with foreign officials, with Giuliani’s lobbying for Ukraine to launch a probe into Democrat Joe Biden having been of concern to the Ukrainian government.

The letter, sent by Vindman’s attorney David Pressman to Fox News‘ legal counsel and posted online by news organisations, accuses the network of broadcasting a defamatory falsehood.

Pressman writes in the letter that under US law espionage is a capital offence, punishable by death.

„Prior to Fox News‘ publication of the Segment, LTC Vindman had never in his decorated 20-year career of service to his country been accused of having dual loyalties or committing espionage. Fox News‘ report on LTC Vindman sparked a torrent of republications and copycat false charges,“ wrote Pressman in the letter.

Many of the claims relate to the fact that Vindman was born in Ukraine, with his family emigrating to the US when he was three-years-old.

It details how conservative activists, including Trump’s son, Donald Trump Jr., and Fox News host, Tucker Carlson, repeated the smear of Vindman’s dual loyalty.

On November 19, President Donald Trump himself retweeted a message from his director of social media, Dan Scavino, alluding to the claim.

The tweet contained a clip of Vindman’s congressional testimony in which he was asked by a Republican lawmaker about being offered the job of Ukrainian defense minister, in a seeming bid to question his loyalty to the US.

Vindman said he rejected the offer and reported it to his superiors. The Ukrainian official who made the offer told the Daily Beast it was made in jest.

The president had previously attacked Vindman as a „never Trumper,“ or anti-Trump establishment Republican, promising to provide evidence to substantiate the claim that has yet to materialise.

Trump Vindman retweet Twitter

„As a result, LTC Vindman and his family have been forced to examine options, including potentially moving onto a military base, in order to ensure their physical security in the face of threats rooted in the falsehood that Fox News originated,“ Pressman wrote in the letter.

On Wednesday, a US Army spokesman told Insider that if deemed to be at risk, Vindman and his family would be moved to a safe location.

Vindman has become the focus for attacks because of his role in the impeachment probe. In dramatic public testimony on Monday, Vindman told the probe of his concern after hearing Trump demand an investigation into domestic rival Joe Biden during a phone call with Ukraine’s president. Vindman was one of the top security officials patched into the call, which sparked the impeachment probe.

Vindman said he twice reported to NSC officials his concerns about the president’s dealings with Ukraine.

In a statement to the New York Times, Fox News said that „as a guest on Fox News, John Yoo was responsible for his own sentiments, and he has subsequently done interviews to clarify what he meant.“

In a USA Today op-ed, Yoo claimed that he did not label Vindman a spy, but claimed Ukraine was mounting an espionage operation, a claim that Pressman in the letter described as being „as legally irrelevant as it is factually incredible.“