Erin Schaff / The New Y​ork Times

Senator Lindsey Graham put it crisply. “This thing will come to the Senate, and it will die quickly, and I will do everything I can to make it die quickly,” he said. “I am trying to give a pretty clear signal I have made up my mind. I’m not trying to pretend to be a fair juror here.”

Senate Majority Leader Mitch McConnell, speaking to Fox News, was even more explicit. “Everything I do during this, I’m coordinating with White House counsel. There will be no difference between the president’s position and our position as to how to handle this to the extent that we can,” he said. “We have no choice but to take [the impeachment trial] up, but we will be working through this process, hopefully in a fairly short period of time, in total coordination with the White House counsel’s office and the people who are representing the president in the well of the Senate.”

The two senators appear to need a brief remedial course on their constitutional obligations. Article I, Section 3, Clause 6 of the Constitution declares that “the Senate shall have the sole Power to try all Impeachments.” And when the Senate is sitting “for that Purpose, [senators] shall be on Oath or Affirmation.”

The requirement of a special oath for senators sitting as impeachment triers of fact is unique in the document. Senators don’t swear a special oath to engage in the appropriations process or to consider judicial nominations or to propose health-care legislation. They don’t even swear a special oath to consider a declaration of war or an authorization to use military force. But they do when the Senate sits as the trial forum for impeachment, at which point it becomes a non-legislative tribunal with a wholly different institutional purpose and face.

“Before proceeding to the consideration of the articles of impeachment,” according to the standing rules of Senate impeachment trials, “the Presiding Officer shall administer the oath hereinafter provided to the members of the Senate then present and to the other members of the Senate as they shall appear, whose duty it shall be to take the same.”

The oath “hereinafter provided” does not oblige senators to act “in total coordination with the White House counsel and attorneys for the accused”; nor does it commit them to doing “everything I can to make this trial die quickly” and to not “pretend to be a fair juror here.” Rather, the oath that both Graham and McConnell will swear reads as follows: “I solemnly swear (or affirm, as the case may be) that in all things appertaining to the trial of the impeachment of Donald J. Trump, now pending, I will do impartial justice according to the Constitution and laws: So help me God.’’

If reconciling either Graham’s or McConnell’s comments with the text of this oath seems tricky, that’s because there is nothing impartial about what either man said about his role. A trier of fact is not impartial when he declares publicly that he is coordinating positions with the defendant and that there will be no daylight between their stances. There is also nothing impartial about declaring oneself to be, well, not impartial.

So what are we to make of it when two senior senators, one of whom is the Senate majority leader and purports to speak for his party’s caucus, have publicly precommitted themselves to violating the oath they are both constitutionally obliged to take?

To be fair, a number of senators have commented extensively on the evidence and said publicly whether they think the president has committed impeachable offenses. Among McConnell and Graham’s colleagues on the Republican side of the aisle, Senator Ted Cruz flatly declared that the impeachment effort is “going to go nowhere” in the Senate. Meanwhile, Senator Ron Johnson has written that the impeachment inquiry is “a continuation of a concerted, and possibly coordinated, effort to sabotage the Trump administration that began in earnest the day after the 2016 presidential election”—a statement that leaves little doubt as to which way Johnson will be voting in the Senate. And Cruz and Johnson are far from alone among Senate Republicans, many of whom have slammed the upcoming trial in similar language.

Democrats have been commenting, too. Senator Elizabeth Warren has been among the most outspoken: “Of course I will,” she answered when asked during the November Democratic presidential debate whether she would vote to convict Trump. Among her fellow presidential candidates, other serving senators are somewhat more circumspect but have nevertheless left little doubt about which way they will vote. Senator Cory Booker, for example, said after the House Judiciary Committee vote on articles of impeachment that “this president violated his oath and eroded the trust of the American people—it’s our moral obligation as jurors in the Senate to proceed in this solemn process in an honorable and deliberate way.”

But declaring, or hinting, that the evidence is adequate or inadequate for removal is a step short of outright promising to be unfair or to coordinate positions with the White House. While forward-leaning comments by senators are, in our view at least, inappropriate, one might defend them on the grounds that much of the evidence is uncontested. So Warren might have an argument that, say, the uncontested facts justify a removal vote, so no possible presentation of evidence at the trial could persuade her to vote otherwise. And Cruz and Johnson might conversely take the view that, even assuming the worst, they know what they think and there are no circumstances in which they would vote to convict.

It is actually not obvious what the optimal amount of senatorial comment on the merits of the matter looks like. Senators have different obligations, after all. Quite independent of their role as triers of fact in impeachment trials, they have oversight obligations with respect to policy toward Ukraine. They also have obligations to protect civil servants—such as the whistle-blower whom the president seems dead set on attacking at every opportunity. And they are responsible for appropriating the military aid to Ukraine held up by the president, and for protecting Americans against civil-liberties abuses by the executive branch—such as improper investigations initiated for political gain. They are also political animals charged with representing their constituents and, more crassly, concerned with protecting their seat in the Senate come election time. So it’s both wrong and somewhat naive to think that senators—like jurors in a criminal proceeding or a judge presiding over a case—should refrain from any comments with respect to matters that could come before them.

What they probably should do, however, is avoid prejudging the evidence or how they are going to vote. Senator Mitt Romney’s comments on the impeachment trial are a decent model of what such restraint looks like: “There will be a trial in the Senate,” he has commented, and “we will hear the arguments from both sides. Upon those arguments, and whatever evidence they present, I'll make a decision.” This has not stopped Romney, however, from commenting on substantive matters connected to the Ukraine scandal and criticizing the president’s conduct. Other senators have taken a similar approach, though perhaps not quite as sphinxlike: Democratic Senator Sherrod Brown, for example, commented that Trump “did things Richard Nixon never did” but insisted that senators should decide whether to convict the president “based on the evidence.”

Of course, Romney faces an unusual political calculus: He was elected in a largely Republican state where the president is nevertheless relatively unpopular, and he has walked the knife-edge of criticizing the president without straying too far from the GOP flock. And there is a thin line between Romney’s statement—which looks principled—and those of senators such as Susan Collins, who has refused to weigh in on the Ukraine scandal at all on the grounds that she takes her role in the Senate trial “really seriously,” which can start to shade into cowardice. But the fact that the vectors of political pressure push different senators in different directions is a reflection of how the Constitution designates impeachment as a political, as well as a quasi-judicial, process.

Whatever the right answer is, what Graham and McConnell have done—publicly committing themselves to behaving in a fashion inconsistent with their oath—is certainly the wrong answer. Any honest approach to the difficult question of the Senate’s role in the impeachment trial has to acknowledge the tension between the political and judicial aspects of impeachment. Graham and McConnell, however, have resolved that tension by declaring that the nonpolitical components of the trial just don’t matter. Merely setting the comments alongside the oath both men will have to swear reveals their lawless nature. And as if to drive that irony home, among the charges against the president that the two will evaluate at the Senate trial is the House’s accusation that Trump acted in violation of his own oath to preserve, protect, and defend the Constitution.

So what remedy is available for this constitutional infidelity? There is no penalty, other than political punishment, for senators who flagrantly violate their oath—at least not if they do so in a fashion that doesn’t otherwise violate some law. Just as if McConnell and Graham were to announce that they will preserve and protect the Constitution from all enemies foreign and domestic unless those enemies are Trump supporters, the remedies here are entirely political.

Writing the other day in The Bulwark, Bill Kristol and Jeffrey Tulis suggested that a small group of Republican senators could join with Democrats to make the trial operate appropriately:

If three or more Republican senators now join Democrats in insisting that the trial be structured to be the kind of full and fair trial anticipated by the Constitution and by the Senate Rules on Impeachment Trials, they can do a lot to make a fair trial happen.

A small number of responsible Republican senators—probably only three, in fact—could form a constitutional caucus.

Kristol and Tulis are correct on this point, but what they propose is not a complete remedy for the corruption Graham and McConnell are promising. It is a remedy, rather, against some of the effects of that corruption—that is, a means of protecting the possibility of an honest trial in the face of the promises the two senators have made to scupper it.

A constitutional caucus would not address the conduct of these two senators, their votes, and their lobbying of their colleagues. The full remedy for their behavior, rather, is the same as that for the oathless president whose actions will soon be on trial. It lies in holding up what they say they are going to do against the text of the oath they will swear. And it lies in mocking them for the yawning gap between the two—and hoping the people of their states might care.

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