Attorney Alan Dershowitz, a member of President Donald Trump's defense team, alarmed Democrats and many legal scholars with his argument in the first day of questions and answers in the Senate impeachment trial that presidents cannot be removed from office for an action they believe could help get them reelected.

Dershowitz said Thursday that his answer is being "willfully distorted."

In response to a question from Sen. Ted Cruz, R-Texas, about whether it mattered if Trump engaged in a "quid pro quo," Dershowitz said motive was what mattered and if an act was in the public interest, it was not impeachable. And he said it was reasonable for a public official to equate what is in their own political interest with the public good.

"Every public official that I know believes that his election is in the public interest," he said. "And if a president does something which he believes will help him get elected in the public interest, that cannot be the kind of quid pro quo that results in impeachment."

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Dershowitz said a quid pro quo that involved an illegal act, or was done for personal financial gain, would be impeachable, however.

Trump is facing two articles of impeachment, one on a charge of abuse of power and one for accusations of obstruction of Congress, stemming for allegations he leveraged military aid to Ukraine in a "quid pro quo" – a Latin phrase for a deal in which something is given and received – with Ukraine for assistance with politically motivated investigations.

Dershowitz went on to say it was "dangerous" to base an impeachment on assumptions about what a president was thinking when he or she made a controversial decision because "everybody has mixed motives."

"A constitutional impeachment based on mixed motives would permit almost any president to be impeached," he argued. "How many presidents have made foreign policy decisions after checking with their political advisers and their pollsters?"

Amid a flood of criticism on social media and cable news, the high-profile attorney and law professor elaborated on his answer in a series of tweets.

"They characterized my argument as if I had said that if a president believes that his re-election was in the national interest, he can do anything. I said nothing like that, as anyone who actually heard what I said can attest," he said.

Dershowitz said he was responding to the House impeachment managers’ "claim that any electoral benefit would constitute an impeachable quid pro quo." He said his point was that a president could act out of motives that were in the national interest, as well as in his or her own political interest.

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On Thursday, lead House impeachment manager Rep. Adam Schiff, D-Calif., said Dershowitz's reasoning represented a "descent into constitutional madness." He said it amounted to accepting "the premise that a president essentially can do whatever he wants, engage in whatever quid pro quo he wants."

"That is the normalization of lawlessness," he said. "I would hope that every American would recognize that it's wrong to seek foreign help in an American election."

"Make no mistake: the argument by the president and his lawyers that it is somehow OK to accept assistance from a foreign government is an open invitation to Russia, China, and other adversaries to interfere in future elections," Sen. Mark Warner, D-Va., said Thursday.

Harvard Law professor Laurence Tribe, a longtime critic of both Trump and Dershowitz, compared the argument to French King Louis XIV's declaration, "L'état, c'est moi," meaning, "the state, it is I."

"Accepting this argument would put us on a short path toward dictatorship, benevolent or otherwise. It’s incompatible with the government of, by, and for the people. It’s government by egomania," Tribe said on Twitter.

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University of Michigan law professor Barbara McQuade called Dershowitz's logic "absurd" and said, "If the Senate is to maintain any semblance of a check on presidential abuse, surely it must reject this argument."

Former White House counsel John Dean said that by Dershowitz's logic, President Richard Nixon would not have been subject to impeachment for the Watergate break-in.

"Alan Dershowitz unimpeached Richard Nixon today. All Nixon was doing was obstructing justice and abusing power because he thought he was the best person for the USA to be POTUS," Dean said in a tweet.

Hillary Clinton, the 2016 Democratic presidential nominee, also invoked Nixon in a tweet criticizing Dershowitz.

"Richard Nixon once made this argument: 'When the president does it, that means that it is not illegal.' He was forced to resign in disgrace. In America, no one is above the law," she said.

Dershowitz said "of course" Nixon was impeachable.

"He committed numerous crimes: obstruction of justice; witness tampering; destruction of evidence; suborning perjury and more," he said.

Sen. Tammy Duckworth, D-Ill., told MSNBC Dershowitz's claim "sounds like something coming out of North Korea, not Pennsylvania Avenue."

"Dear @CongressEthics: Can I have my staff pressure a foreign government to help my re-election campaign because it’s in the public interest that I get re-elected? Just kidding," quipped Rep, Ted Lieu, D-Calif. "Unlike @realDonaldTrump & crazy @AlanDersh, I follow federal law."

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Rep. Andy Biggs, R-Ariz., defended Dershowitz and said the "the left," and some members of the news media, "blatantly misconstrue" his argument.

"He's never argued that the POTUS has absolute immunity," Biggs said in a tweet. "He's challenging the amorphous charge of Abuse of Power. Huge difference."

The second of the two days scheduled for questions and answers in the Senate impeachment trial opened Thursday afternoon.