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Esteemed law professor Laurence Tribe warned CNN viewers Tuesday that if they truly want President Trump impeached, they must focus on major abuses of power instead of nitpicking every minor incident.

“If you’re going to shoot him, you have to shoot to kill,” Tribe told CNN’s anti-Trump morning show host Chris Cuomo. “And that requires an overwhelming majority of a bipartisan kind. Otherwise you’re just going to nick the guy, and make him feel empowered and vindicated.”

He later apologized. “In an otherwise good interview I made a terrible word choice, saying an impeachment 'bullet' can only be 'shot once' so one must 'shoot to kill.' I wasn’t speaking literally, but as one who works hard to reduce gun violence this was just inexcusable. I’m very sorry,” he tweeted.

Tribe, a law professor at the prestigious Harvard University who has close ties to President Obama, was on CNN to promote his new book, To End a Presidency: The Power of Impeachment.”

He said that impeachment is "really about abusing the authority that we give to high officials” such as President Trump.

“It’s not about garden variety crime. If it turns out, as I wouldn’t be surprised to find, that Donald Trump has been guilty of tax evasion, that may be a crime, but it’s not an impeachable offense."

— Harvard Law professor Laurence Tribe

Cuomo noted that Tribe warns Democrats not to rush down the road of impeachment when dealing with President Trump, but the book also offers an “interesting take” on how to get POTUS removed from office.

It’s not about garden variety crime. If it turns out, as I wouldn’t be surprised to find, that Donald Trump has been guilty of tax evasion, that may be a crime, but it’s not an impeachable offense,” Tribe explained.

Tribe said, on the other hand, that if Trump used “the powers of the United States government to cover up his own criminality or to cover up the way in which he cooperated with Moscow in order to win the presidency, that may or may not qualify as an ordinary federal crime -- but it’s certainly an impeachable offense.”

The professor continued offering liberal fan fiction while going unchallenged by Cuomo on examples of what would be an impeachable offense: “Or, if he decides, ‘I’m simply not going to protect the United States from foreign attack. I’m busy making money.’”

Tribe said the power of impeachment will only be available if it’s not used “loosely” every time something looks amiss.

“You can’t be the boy who cried wolf and have a viable impeachment power. You can’t use it over and over again against the same president,” he said.

Cuomo then quoted Tribe, saying Trump would be a “wounded and dangerous tiger” if there is an attempt to impeach him before the majority of Americans are onboard.

“The book is a must read,” Cuomo said to end the segment.

Tribe was such an influential constitutional scholar that the New Yorker referred to him as the “tenth Justice” to the Supreme Court back in 1996. However, the same publication asked if he sold out amid a series of controversies in 2015.

Fox News' Mike Arroyo contributed to this report.