Newt Gingrich, former speaker of the U.S. House of Representatives, speaks during the 41st annual Conservative Political Action Conference in March  2014.
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Story highlights

Newt Gingrich was a vocal advocate for Trump during his campaign

The former House speaker called the investigation into Trump a "witch hunt"

(CNN) —  

Former House Speaker Newt Gingrich said Friday that it’s impossible for President Donald Trump to obstruct justice because of the fact that he’s president.

“Technically, the President of the United States cannot obstruct justice,” Gingrich said at the National Press Club in an event to promote his new book, “Understanding Trump.” “The President of the United States is the chief executive officer of the United States. If he wants to fire the FBI director, all he’s got to do is fire him.”

However, Gingrich himself has in the past voted to impeach a president over such charges. While speaker of the House, Gingrich voted in 1998 to impeach President Bill Clinton on charges of obstruction of justice and perjury.

Now, with a Republican in power, Gingrich has changed his tune. On Friday he called the investigation into Trump a “witch hunt.”

“The left right now is engaged in the Salem witchcraft process of, ‘We know somebody’s evil, we know somebody’s bad. I wonder who we should burn at the stake? Maybe it’s you, whoever you are,’” Gingrich said. He encouraged the audience to read Arthur Miller’s “The Crucible,” saying “that’s the mentality of the left right now.”

Gingrich was a vocal advocate for Trump during his campaign and at one time was considered for the vice president slot. He said a reported investigation of Trump for obstruction of justice in the Russia probe – which Trump himself said is happening – is related to a failed attempt to prove election collusion between the Trump campaign and Russia, which Gingrich called the “Russia Fantasy.”

“Everybody on the left has been walking around town chanting, ‘watch for the Russian connection, watch for the Russian connection, look for the collusion,’” Gingrich said. “Turns out, even Dianne Feinstein, the ranking Democrat on the (Senate) intelligence committee, says there is zero evidence of collusion. So now the newest one is, ‘Ah, but there was obstruction of justice over the collusion.’”

Gingrich said he has cautioned many in the Trump administration about the seriousness of the current investigations.

“I keep telling everybody at the White House, this is not like New York real estate law, this is criminal law,” he said. “These people are coming after you to put you in prison, and you need to be very careful and you need to listen to your lawyers, and I say this as much to the President as anybody; this is not a game.”

Gingrich raised eyebrows earlier this week when he appeared to blame liberal rhetoric for the shooting at a GOP congressional baseball practice Wednesday that left five, including Majority Whip Steve Scalise of Louisiana, wounded and the gunman dead.

Speaking on Fox News’ “Outnumbered,” Gingrich said, “It’s part of a pattern. You’ve had an increasing intensity of hostility on the left.”