Constitutional scholar and criminal defense lawyer Alan Dershowitz rose to the defense of President Donald Trump at his Senate impeachment trial on Monday evening, arguing that the conduct with which Trump had been charged was outside what the Framers of the Constitution had considered to be impeachable offenses.

Dershowitz drew upon the successful 1868 arguments by former Supreme Court Justice Benjamin Curtis, who had dissented from the infamous Dred Scott decision and resigned from the Court in protest, and who later defended President Andrew Johnson in his impeachment trial, the first ever of any U.S. president.

Impeachment, Dershowitz argued, required “criminal-like conduct akin to treason and bribery.” He stressed: “This is the key point in this impeachment case … purely non-criminal conduct including ‘abuse of power’ and ‘obstruction of Congress’ [the charges against Trump] are outside the range of impeachable offenses.”

He said claims by Democrats like Rep. Maxine Waters (D-CA), who said the House could do what it wanted, were wrong: “It would place Congress above the law. It would place Congress above the Constitution. … would be for Congress to do what it is accusing the president of doing. And no one is above the law.”

Dershowitz said that the House impeachment managers had erred in arguing that the general fears of the Framers that a president would abuse his power could be substituted for the criteria written in the text of the Constitution itself, which sought a specific basis for impeachment and removal of judges and presidents.

He then reviewed the debates among the Framers of the Constitution about how impeachment should be handled, noting in particular that James Madison feared the term “Misdemeanors” in “High Crimes and Misdemeanors” would be abused (as had been in the case against President Trump, Dershowitz argued).

He noted that the impeachment power was narrow enough that originally a president could not even be removed for mental and physical incapacity until the 25th Amendment was passed in the 20th century. Dershowitz noted that part of the reason the Constitution left that out was “incapacity” is not criminal.

The Harvard Law professor emeritus cited the 18th-century legal authority William Blackstone, whose definition of “misdemeanor” called it a synonym for “crime,” not a minor offense. And Dershowitz noted that Alexander Hamilton — cited by the Democrats — saw impeachment as akin to a criminal law process.

Hamilton’s words in Federalist 65, Dershowitz said, calling impeachment “political” in nature, were often misconstrued to expand the criteria for impeachment beyond “High Crimes and Misdemeanors.” Instead, Dershowitz said, Hamilton meant to contract impeachment to offenses that also implicated public conduct.

Dershowitz went on to point out that “abuse of power” is too loose a standard for impeachment — implying, as James Madison said about “maladministration,” that presidents would serve at the pleasure of the Senate. He gave several examples of critics accusing presidents, including Barack Obama, of “abuse of power.”

He pointed out that all politicians act not just in the public interest, but with a view to their own re-election. He said that the House impeachment managers’ argument that the president could be impeached based on what was in his mind was an absurd standard — one that no one would want to be judged by themselves.

Dershowitz said that even if Democrats could show that Trump had asked a foreign power to intervene in the American election on his behalf, that would itself be impeachable. A “quid pro quo alone is not a basis for abuse of power,” but part of the way presidents had conducted foreign policy since the country’s founding.

Then Dershowitz turned to the media’s obsession for the day — the accusation in a New York Times article on Sunday evening that alleged that former National Security Advisor John Bolton had written a draft book in which he said Trump wanted to condition aid to Ukraine on it conducting investigations into “Democrats.”

Even if, for argument’s sake, everything in the Times article were true, Trump could not be impeached. A mere “quid pro quo,” Dershowitz said, required criminal-like conduct. You could not, Dershowitz said, turn “conduct that is not impeachable into impeachable conduct simply by using words like ‘quid pro quo’.”

He added that it could not be “obstruction of Congress” merely to invoke Constitutional powers available to the president. The problem, ultimately, with “words like ‘abuse of power’ and ‘obstruction of Congress'” is that they are “standard-less,” substituting subjective political and partisan criteria for clear principles.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. He earned an A.B. in Social Studies and Environmental Science and Public Policy from Harvard College, and a J.D. from Harvard Law School. He is a winner of the 2018 Robert Novak Journalism Alumni Fellowship. He is also the co-author of How Trump Won: The Inside Story of a Revolution, which is available from Regnery. Follow him on Twitter at @joelpollak.