The Chief Justice is a former clerk to Rehnquist, so we should look for him to tread lightly in his predecessor’s footsteps.
Over the past three weeks of this series, I have set forth the evidence of the original public meaning of the Constitution’s impeachment standard of “high Crimes and Misdemeanors.” The English backdrop understanding and practice of four centuries of impeachment proceedings, often employing this very language; the conscious decisions of the Constitutional Convention to grant a broad impeachment power, to draw upon the English practice and understanding, and to adopt this known, familiar term-of-art in preference to other formulations; the evidence from The Federalist papers explaining impeachment and confirming this understanding; and the confirming ratification-debate evidence of this understanding from statements made in state ratifying conventions, in the First Congress, and the earliest legal commentary, all point to a broad understanding of the impeachment power. (Early impeachment practice is more mixed and inscrutable, and at all events constitutes less reliable evidence of the objective, original meaning of the Constitution’s language.)
It is possible to glean from this evidence several general categories of offenses, all of which fit within the legitimate constitutional bounds of the impeachment power. The decision as to whether to impeach and convict an executive (or judicial) officer lies within Congress’s good faith judgment within these bounds. In addition to the per se impeachable offenses of “Treason” and “bribery,” the House and Senate properly may employ the impeachment power to punish or remedy what they determine to be:
(1) Serious (or serial) violation of the Constitution or departure from sworn constitutional duty (i.e., violation of one’s oath of office), as judged by the two houses of Congress;
(2) Misuse or abuse of constitutional powers actually possessed (again, as judged by the two houses of Congress):
(3) A serious failure in performance of the constitutional responsibilities of executive or judicial office, whether by affirmative acts or by wrongful omissions, evidencing culpable negligence or incompetence (again, as judged by the two houses of Congress);
(4) Betrayal, compromise, or abandonment of the national interest, disloyalty falling short of treason, or an intolerable conflict of interest between an officer’s personal or financial interests and the duties of office (as judged by the two houses of Congress);
(5) Violation of the public trust or breach of faith, by dishonesty or lack of integrity in public behavior, self-dealing or corrupt conduct in any of a variety of forms (such as receiving or giving kickbacks or payoffs, or the dishonest use of funds or awarding of public benefits, short of “bribery” per se);
(6) Serious, willful criminal-law violations of a nature that Congress judges incompatible with continuance in important national office, whether or not involving the use of the powers of office in any respect, whether or not committed while holding office, and whether or not punished or punishable by the ordinary processes of criminal-law enforcement; and
(7) Serious non-criminal misconduct or misbehavior that the two houses of Congress judge to be incompatible with the function, purpose, or dignity of the office, including such things as sexually predatory behavior, or misuse of office for personal gain, pleasure, or entertainment.
Each of these sub-categories of wrongful, culpable misconduct fits within the broad range of meaning afforded by the Constitution’s term “high Crimes and Misdemeanors.” To be sure, the standard is sufficiently broad as to call for a measure of sensible practical judgment and good faith discretion by Congress. But in terms of the Constitution’s meaning – the breadth and sweep of the power of impeachment conferred by the document itself, it is hard to avoid the conclusion that all offenses of the above description fairly fall within the overall heading of “high Crimes and Misdemeanors,” as that term was employed and understood at the time of the Constitution’s adoption.
Constitutional Power and Constitutional Judgment
This is a broader understanding of the scope of the impeachment power than is conventionally and popularly recognized. Indeed, it is true that the nation’s constitutional practice with respect to impeachment has fallen considerably short of the full scope of the meaning of the Constitution’s grant of the impeachment power. Neither fact changes the conclusion as to the scope of the constitutional power itself.
The fact that many persons may have come to view the impeachment power as narrower than the Constitution in fact allows, or may hold mistaken understandings of its full scope, does not matter to the existence and extent of the constitutional power itself. It testifies only to mistaken views and flawed understandings. Where popular or conventional understanding is incorrect, it is that understanding that needs to change – not the meaning of the Constitution.
The fact that actual practice has fallen short of actual constitutional meaning is also beside the point. Contrary practice does not alter the meaning of the Constitution. Where practice has departed from the Constitution, it is once again the practice that should be changed, not our understanding of the Constitution.
Obviously, application of these broad categories in specific instances calls for judgment and discretion. What all appropriately may enter into that judgment? That is not an entirely easy question. But it is easy enough to begin with certain considerations that clearly should not form part of the exercise of such judgment and discretion – and then think about what properly remains.
First, as suggested by the above, mistaken views of the scope of the constitutional power of impeachment itself – errors of constitutional understanding – do not properly form any part of the judgment concerning whether wrongdoing warrants impeachment. Simply put, ignorance is not an exercise of judgment. The erroneous belief that an official cannot constitutionally be impeached or convicted forms no legitimate part of the exercise of “discretion” as to whether he or she should be. All the more clearly, knowing, deliberate misrepresentation of the scope of the power does not properly inform an element of legitimate judgment concerning its exercise.
Second, bare partisan loyalties should form no part of the impeachment judgment (in either direction – whether in favor of or opposed to an impeachable official). Neither should assessment of one’s party’s political fortunes, the general level of popularity or political support of the official in question, or the suspected partisan motivations of those on the other side form part of the impeachment judgment. If the seriousness of the wrongdoing otherwise merits removal, such low-political implications ought never bar it; and if the seriousness of the wrong does not warrant removal, such ordinary political considerations do not justify it. It is fair to observe that this principle seems frequently to be honored in the breach: both Democrats’ defense of Clinton and Republicans’ defense of Trump can be criticized on this score. And it is fair to observe that partisan motives might affect the willingness of a president’s political opponents to bring both meritorious and unmeritorious charges. My point is that the charges always should be evaluated on their own merits – judged to be constitutionally impeachable or not and then judged serious enough or not to justify use of the constitutional power – not on the basis of political incentives, political consequences, or assessments of the calculations or motives of the other side on this score.
It is not even clear to me that a partisan-motives-driven willingness to bring or consider merited impeachment proceedings is at all a bad thing. It strikes me that partisan-loyalty-driven Stalingrad defenses of a president whose misconduct otherwise merits impeachment is a far worse problem. To misquote Madison’s Federalist 51, in the former situation partisan interest might supply “the defect of better motives”: it urges a right course of conduct for arguably wrong reasons. In the latter case, partisan interest supplies nothing but defect: it urges wrong outcomes for wrong reasons.
Incidentally, the problem of low-partisanship is neither new nor was it unforeseen by the framers. Hamilton anticipated it in Federalist 65, even as he disapproved it: impeachment, he wrote,
will seldom fail to agitate the passions of the whole community, and to divide it into parties more or less friendly or inimical to the accused. In many cases it will connect itself with the pre-existing factions, and will enlist all their animosities, partialities, influence and interest on one side or on the other; and in such cases there will always be the greatest danger that the decision will be regulated more by the comparative strength of parties than by the real demonstrations of innocence or guilt.
And that danger was more likely to be the protection of popular, but guilty, elected officials by members of their own party. Malefactors would be “too often the leaders or the tools of the most cunning or the most numerous faction” and thereby have the support of the public and, crucially, of members of their own party – including in the legislature. Party loyalists “on this account can hardly be expected to possess the requisite neutrality toward those whose conduct may be the subject of scrutiny.”
To repeat: Hamilton was describing harsh practical political reality, not embracing it as correct. The correct stance is that such manifestations of partisanship are wrongful, improper corruptions of impeachment judgment.
Third – and this one I will concede might be somewhat more arguable, at least in extreme circumstances – the impeachment judgment should not be concerned with either the collateral policy implications, large or small, of impeachment and removal or with the merits of the officer who would replace a removed official. Again, the judgment should be on the merits of the assessed seriousness of the misconduct proven, not these collateral political judgments. While one recoils at the prospect of impeachment of a Lincoln in the midst of civil war, or of FDR in the midst of world war, the point of principle remains the same: if the conduct itself, in context, is impeachable and serious enough to warrant that remedy – which, for reasons explained below, I think it was not, with respect to either president – even important collateral consequences, like the removal of an (otherwise) “great” president, should not form part of the impeachment judgment.
In the case of a president, that’s what vice presidents are for. The original Constitution provided for exactly this contingency, and the Twelfth Amendment, adopted in 1804, now usually works to insure that vice presidents generally share the political views of the presidents with whom they are elected. There are exceptions, to be sure, and vice presidents are not always the equivalent in skill, savvy, or leadership qualities of the presidents whom they would replace. (Andrew Johnson was surely no Lincoln; Truman was no FDR.) But that is part of our constitutional system, just as impeachment is.
In short, impeachment was designed with the idea in mind that presidents sometimes might warrant removal from office. Of course this can have serious practical policy consequences. But the Constitution provides for succession in part for exactly this reason. To say that any particular president is so “indispensable” as to be unimpeachable is to say that such a president really is above the law and not answerable to the Constitution.
What Should Inform the Constitutional Judgment Concerning Impeachment?
All of this discussion of what should not inform the impeachment judgment suggests what should: an assessment of the seriousness of the impeachable wrongful conduct (action or inaction), considered in context, and considered apart from ordinary political considerations or partisan loyalties (insofar as humanly possible). “Seriousness” is unavoidably a matter of judgment, but it is judgment of a particular sort. It includes not only a judgment as to whether the claimed wrong really was wrong, but also about how wrong it was: whether it worked genuine harm to other persons, to the constitutional system, to the administration of justice or law, or to the national welfare. It may include a judgment as to whether the wrong committed was willful and intentional, or a good-faith mistake or honest disagreement (even if an important one). It may include a judgment as to whether the wrong was isolated and singular or instead reflects a pattern of persistent, insistent wrongful conduct. It may include a judgment as to whether exigent circumstances justified or excused conduct otherwise judged to be seriously wrong.  And in the case of a criminal-law offense, such judgment might involve assessment of whether the offense was a technical, legal wrong not involving moral culpability or bad faith – a crime (in common law terms) malum prohibitum but not malum in se – or an act of clear moral turpitude.
In all respects, however, the relevant judgment concerns the seriousness of the wrong(s) committed, not an overall assessment of the political merits of an official generally or of the policy implications of his or her impeachment and removal. The latter course is less one of legitimate impeachment-power discretion than of impeachment nullification, akin to the actions of a judge or jury that dishonestly acquits a guilty accused not because the accused is thought to have done nothing seriously wrong but because the judge or jury wishes to let the defendant off the hook notwithstanding his or her wrongdoing, for extraneous political reasons. 
To allow into the judgment of impeachment an assessment of collateral political consequences of impeachment is to let in, so to speak through the backdoor, the wrongful notion of impeachment as a mere vote of confidence or no-confidence in a president: that presidents whose policies or personality we like should be kept, impeachment-worthy or not. That really does, perversely, make the president’s retention in office a measure of (in James Madison’s words) the “pleasure of the Senate.” True, a president would not be removed at the pleasure of the Senate. But he would be retained – no matter his wrongdoing – if he retained the political pleasure of his party in the Senate, in sufficient numbers to constitute a blocking one-third-plus-one vote. Such a dynamic would turn the president into a de facto prime minister, not truly subject to constitutional or other constraints on his power, but accountable for his actions only to his party in Congress as long as that party retained minimal support.
So that’s the core of it: the constitutional categories fitting the standard of “high Crimes and Misdemeanors” within the original meaning of the Constitution; and the general criteria for appropriate constitutional judgment concerning the application of that standard.
I will turn next to the principal objections typically raised to such a broad understanding of the impeachment power. I will then apply the above principles to the nation’s three leading historical cases of actual or threatened presidential impeachment – Andrew Johnson, Richard Nixon, and Bill Clinton – and to the situation presented today.
 Wartime exigency or emergency might in some instances excuse – or even justify – acts that might otherwise properly be regarded as impeachable usurpations of power or violations of rights. In 2004, I defended the propriety of some of Lincoln’s actions on these grounds. For reasons explained in that article, I consider the Japanese Internment harder to defend on the merits. Nonetheless, FDR’s culpability arguably is lessened by the circumstances of believed wartime exigency, incomplete information, congressional and judicial endorsement, and badly misleading military advice. I believe FDR should be condemned for his actions, but should not have been impeached for them.
 This was exactly the shameful explanation given by Senator Robert Byrd for his vote to acquit Bill Clinton, in his infamous remarks acknowledging Clinton’s guilt as charged, acknowledging that Clinton’s actions constituted impeachable offenses, acknowledging that the offenses committed were serious enough to warrant removal, but stating that political considerations suggested the “wisdom” of leaving Clinton in office.