President Donald Trump‘s star impeachment defense attorney, Alan Dershowitz, tried to clarify his arguments from Wednesday that anything a president does to get reelected is not impeachable.

The Harvard law professor was missing from the Senate floor Thursday, after making an argument that has come under fire by several constitutional law experts.

On Wednesday, he said if a “hypothetical” president pressured a foreign country to build a hotel with their name on it, it would clearly be an act of corruption. But if their actions were part of an attempt to get reelected, they would be acting in the “national interest.”

“But a complex middle case is ‘I want to be elected. I think I’m a great president. I think I’m the greatest president there ever was and if I’m not elected, the national interest will suffer greatly,'” Dershowitz said to the Senate. “That cannot be an impeachable offense.”

He attempted to clarify his comments Friday, saying he never said that “a president can do anything if he thinks his election’s in the national interest.”

“I never said, never suggested and it was a total distortion — not misunderstanding – distortion of my point that I think a president can do anything if he thinks his election’s in the national interest. Never said it. It’s nonsense.”

On Friday, Senate Minority Leader Chuck Schumer (D-New York) tore apart Dershowitz’s argument, saying that by that logic, “President Nixon did nothing wrong in Watergate. He was just breaking into the DNC to help his reelection, which of course is in the public interest.”

He also acknowledged Dershowitz’s television appearances.

“I hear he’s correcting it on TV today,” Schumer said. “But that seems to be Mr. Dershowitz’s pattern. He gives a statement on the floor and then spends the next day correcting it. What a load of nonsense.”

Dershowitz responded to Schumer’s interpretation of his argument on Twitter, saying Nixon was impeachable because he “committed numerous crimes.”

His argument that an impeachable must be an indictable crime, as in the case of Nixon, has been challenged by several legal scholars.

Frank Bowman, a University of Missouri law professor and former student of Dershowitz’s at Harvard Law School, called the idea “rubbish” to PBS Newshour.

Jonathan Turley, a George Washington University law professor who argued to the House against impeachment, wrote in a Washington Post op-ed that such an argument was “politically unwise and constitutionally shortsighted.”

“The developing defense by the White House is also a mistake,” Turley wrote. “It would again ‘expand the space for executive conduct’ by reducing the definition of impeachable conduct to the criminal code. It is an argument that is as politically unwise as it is constitutionally shortsighted.”