I think the answer is eight — eight thematic areas, most of which include more than one violation.
In making the list, I erred on the side of conservatism. I excluded gray areas from the Mueller report, like the Trump campaign's flirtation with Russian operatives. I also excluded all areas of policy, even the forcible separation of children from their parents, and odious personal behavior, like Trump's racism, that doesn't violate the Constitution.
Yet the list is still extensive, which underscores Trump's thorough unfitness for the presidency. He rejects the basic ideals of American government, and he is damaging the national interest, at home and abroad. Here's the list:
1. Obstruction of justice
Both the Nixon and Clinton articles included the phrase "prevented, obstructed, and impeded the administration of justice," and Trump's impeachment should start with his pattern of obstructing investigations.
He has admitted that he fired the FBI director to influence the investigation of his own campaign. He has harassed Justice Department officials who are Russia experts, including Andrew McCabe and Bruce Ohr. Trump also directed his White House counsel to lie about their conversations over whether to fire Robert Mueller. Most recently, the White House tried to hide evidence about Trump's phone call with Ukraine's president, by improperly classifying material about it.
2. Contempt of Congress
Another article of impeachment against Nixon said that he had "failed without lawful cause" to cooperate with a congressional investigation. Trump has gone much further than Nixon, outright refusing to participate in the constitutionally prescribed impeachment process. As a result, the country still doesn't know the full truth of the Ukraine scandal.
3. Abuse of power
The House will almost certainly adopt a version of this article, impeaching Trump for turning American foreign policy into a grubby opposition-research division of his campaign.
The most haunting part is that if a courageous whistleblower hadn't come forward, Trump most likely would have gotten away with it. He would have pressured the Ukrainian government to announce an investigation of the Bidens, and we in the media would have played along, producing the headlines that Trump wanted to see.
4. Impairing the administration of justice
That phrase appears in the second impeachment article against Nixon, which detailed his efforts to use the IRS, FBI and others to hound his opponents. It's a version of abuse of power — but distinct from the previous item because it involves using the direct investigatory powers of the federal government.
Trump has repeatedly called for investigations against his political opponents, both in public and in private with aides. For example, as the Mueller report documented, he pressured Jeff Sessions, then the attorney general, to investigate Hillary Clinton: "You'd be a hero," Trump said. This behavior has violated the constitutional rights of American citizens and undermined the credibility of the judicial system.
5. Acceptance of emoluments
The Constitution forbids the president from profiting off the office by accepting "emoluments." Yet Trump continues to own his hotels, allowing politicians, lobbyists and foreigners to enrich him and curry favor with him by staying there. On Sunday, William Barr, the attorney general, personally paid for a 200-person holiday party at Trump's hotel in downtown Washington.
The Democratic-controlled House has done an especially poor job of calling attention to this corruption. It hasn't even conducted good oversight hearings — a failure that, as Bob Bauer, a New York University law professor and former White House counsel, told me, "is just astonishing."
6. Corruption of elections
Very few campaign-finance violations are impeachable. But US$280,000 in undisclosed hush-money payments during a campaign's final weeks isn't a normal campaign-finance violation. The 2016 election was close enough — decided by fewer than 80,000 votes across three swing states — that the silence those payments bought may well have flipped the outcome.
7. Abuse of pardons
The president has wide latitude to issue pardons. But Trump has done something different: He has encouraged people to break the law (or impede investigations) with a promise of future pardons.
And he didn't do it only during the Russia investigation. He also reportedly told federal officials to ignore the law and seize private land for his border wall, waving away their worries with pardon promises.
8. Conduct grossly incompatible with the presidency
This is the broadest item on the list, and I understand if some people are more comfortable with the narrower ones. But the "grossly incompatible" phrase comes from a 1974 House Judiciary Committee report justifying impeachment. It also captures Trump's subversion of the presidency.
He lies constantly, eroding the credibility of the office. He tries to undermine any independent information that he does not like, which weakens our system of checks and balances. He once went so far as to say that federal law-enforcement agents and prosecutors regularly fabricated evidence — a claim that damages the credibility of every criminal investigation.
You may have forgotten about that particular violation of his oath of office, because Trump commits so many of them. Which is all the more reason to make an effort to hold him accountable.
Written by: David Leonhardt
© 2019 THE NEW YORK TIMES