On May 18, in the first of three long Twitter threads, Rep. Justin Amash (R‑MI) announced his conclusion that “President Trump has engaged in impeachable conduct.” That tweetstorm unleashed a… different kind of storm from his fellow Republicans. The self‐​styled House Freedom Caucus voted unanimously to condemn Amash, an irate Michigan state rep. announced he’d challenge the congressman in the GOP primary, and, of course, there was President Trump, fuming that Amash is “a total lightweight” and “a loser who sadly plays right into our opponents hands!”

About the only GOP officeholder with anything nice to say was Sen. Mitt Romney (R‑UT). Romney made sure to emphasize his disagreement with Amash, but praised him for “a courageous statement.” Coming from the on‐​again, off‐​again Trump critic, “courageous” sounded a bit like a tell (subtext: “I wish I had the guts!”).

Whatever one thinks of President Trump or the other personalities involved, the scope of high crimes and misdemeanors is a constitutional question, and shouldn’t be analyzed through a Red or Blue lens. As I argue in my recent Cato study on impeachment, Indispensible Remedy, if you raise the bar to save a president you like—or lower it to nail one you hate—you may come to regret it when power changes hands.

Amash, who’s long used social media to explain the constitutional reasoning behind the positions he takes, makes a number of claims about the scope of Article II, section 4. As it happens, he has a better grasp of the constitutional issues surrounding impeachment than most of his colleagues on both sides of the aisle. I’ll highlight and elaborate on a few of his key points below.

With his emphasis on “the public trust,” our least Hamiltonian congressman is channelling Alexander Hamilton in Federalist 65. In that essay, Hamilton described impeachment as a remedy aimed at:

those offenses which proceed from the misconduct of public men, or, in other words, from the abuse or violation of some public trust. They are of a nature which may with peculiar propriety be denominated POLITICAL, as they relate chiefly to injuries done immediately to the society itself.

But that broad understanding wasn’t a point much in dispute among the Framers. James Madison described impeachment as an “indispensable” provision for “defending the Community against the incapacity, negligence, or perfidy of the chief Magistrate.” And throughout American history, federal officers have been impeached for offenses ranging from petty corruption, to neglect of duty, to withholding information from Congress, and “behaving in a manner grossly incompatible with the proper function and purpose of the office.” When Amash says that impeachment can extend to “careless, abusive, corrupt, or otherwise dishonorable conduct,” it may sound sweeping, but he’s on solid ground.

Amash says Trump’s defenders are wrong when

He’s right here too. Had the Framers restricted impeachable offenses to crimes, impeachment would have been a dead letter from the start. In the early years of the republic, there were hardly any federal crimes on the books. As Justice Joseph Story noted in 1833, in the impeachment cases since ratification, “no one of the charges has rested upon any statutable misdemeanours.” And throughout our entire constitutional history, according the Congressional Research Service, fewer than a third of the impeachments approved by the House “have specifically invoked a criminal statute or used the term ‘crime.’” (For more, see: “The Overcriminalization of Impeachment”).

In fact, exercises of constitutional powers such as the president’s power to remove subordinate officials and grant pardons, can be grounds for impeachment, even if the president has committed no crime.

The ultimate remedy would be necessary in some cases, the Framers believed, to deter presidents from corrupt misuse of the broad powers the Constitution grants him. Madison, for example, insisted that the president could be impeached for “wanton removal of meritorious officers,” or for using the pardon power to shelter coconspirators. (For more, see Indispensable Remedy, pp. 69–75 and “The Complete Power to Pardon” and “the Sole Power of Impeachment” 

American public intellectuals frequently warn that serious consideration of impeachment in any one case will open a Pandora’s Box, leading to, as Alan Dershowitz puts it, the “weaponization of impeachment as a partisan political tactic to be deployed by both parties.”

There’s very little evidence for that proposition. After the Johnson impeachment we went 106 years without another serious effort to remove a president. In the 45 years since Nixon resigned, we’ve had only one such attempt. The supermajority requirement for removal, combined with the effort it takes to launch an impeachment inquiry and see it through, will always remain a significant disincentive to using the “indispensable remedy” too casually.

What gets far less attention is the risk associated with our longstanding impeachment phobia: that “Congress will employ it so rarely that it cannot deter misconduct.” As Keith Whittington has written, “if Congress tolerates officers who commit high crimes and misdemeanors, it sends a signal to other officers that those crimes are not beyond the pale.” In politics, as in economics, incentives matter: lower the cost of bad behavior and you’ll likely get more of it. Amash is right about that too.