Former FBI director Robert S. Mueller III, the special counsel probing Russian interference in the 2016 election, in Capitol Hill. (Andrew Harnik/Associated Press)
Opinion writer

I grant that it is unreasonable for a member of Congress to rebut and denounce every falsehood that President Trump utters. By The Post’s FactChecker count, that would entail calling out nearly 2,000 false statements in 2017 alone. That said, there is no excuse for allowing the president’s daily assaults on the Justice Department, the FBI and the entire legal system to go  unchallenged.

Trump has picked up where he left off last year. On Tuesday he tweeted, “Crooked Hillary Clinton’s top aid [sic], Huma Abedin, has been accused of disregarding basic security protocols. She put Classified Passwords into the hands of foreign agents. Remember sailors pictures on submarine? Jail! Deep State Justice Dept must finally act? Also on Comey & others.” This is not just gibberish; it’s dangerous and intolerable gibberish.

There is no evidence that Abedin violated any criminal laws. The Justice Department is headed by Trump’s own appointees, including Attorney General Jeff Sessions and Deputy Attorney General Rod J. Rosenstein (who, by the way, remain unacceptably silent when the president impugns their employees’ integrity). There is no basis for any criminal proceedings against former FBI director James B. Comey — although his firing and Trump’s continued efforts at intimidation raise legitimate arguments that Trump has obstructed justice and abused his powers. The incessant drumbeat of threats to imprison his political opponents and to bully a key witness in an obstruction case against him underscore the degree to which his ongoing tenure represents a threat to the rule of law.

Bob Bauer (writing before the tweet) reminds us:

This president brings into his administration an instrumental view of the law that, he believes, served him in his business career. The government lawyers are as his lawyers, much as he is fond of referring to the senior uniformed military leadership as “my generals.” An FBI director who declined to pledge his personal loyalty to Trump lost his job. In the same New York Times interview in which he declared his “absolute” control over DOJ, Trump rated his own attorney general low on the loyalty scale. He believes that a truly loyal attorney general would not have recused himself from the Russia investigation and would not have hesitated to fashion what the president considers an overdue prosecution of Hillary Clinton. As his chief of staff assured the Timesthis president sees existing norms as part of the problem that he “alone” can fix. . . .

Stated differently, this president and his allies have worked to convince the public that the Department of Justice is an organ of the “deep state.” They portray the norm of neutrality as largely a fraud, another tall tale told by the establishment to disregard popular will and maintain the liberal elites in power. A strong president, as Trump aspires to be, is required to assert himself and to require the law enforcement bureaucracy, like the other deep state agencies, to fall into line. It is then open to him to reinterpret or misinterpret the norm—or to seek to discredit it entirely—with lasting impact.

By remaining silent, members of Congress, not to mention high-ranking political appointees, give the president the aura of plausibility, sanity and legitimacy to undermine the impartial administration of justice. They leave it to Democrats to do the hard work of defending our constitutional system, which further politicizes the issue (exactly as Trump hopes) and forfeits their role as good-faith defenders of the Constitution. (“For the norms necessary for the integrity of law enforcement to survive, the government cannot be run by those who generally detest it except and only to the extent that it can be bent to their will,” Bauer cautions. “The nation’s leaders need to know or learn enough about norms to think hard about how to make them perform their function of preserving liberty in a constitutional democracy.”)

We would offer two corollaries to Bauer’s cautionary analysis.

First, Democrats should not be cowed into playing down or ignoring the potential for impeachment. They might rightly or wrongly figure this impairs their chances in the midterms, but it is their obligation to point out in real time the actions that violate the president’s oath of office. When facts are readily ascertainable (from Trump’s own lips and Twitter account), they need to make clear when conduct constitutes an abuse of power. It is the stuff for which impeachment is intended to remedy. Moreover, they cannot hope to spring impeachment on the voters if they take the House. They need now to begin an honest, coherent discussion of the president’s abuse of political powers, including improper use of the pardon power, efforts to intimidate a key witness and threats to fire his own attorney general for acting on his obligation to recuse himself.

Second, Republicans should drop the irresponsible and blatantly false argument that if something is within his constitutional powers (e.g., to issue a pardon), Trump cannot be impeached for abusing his powers. (As a logical matter, then, Richard Nixon could not have been impeached, nor would taking action as commander in chief in exchange for monetary favors from a hostile power be sufficient grounds.)

Bauer’s colleague Jane Chong argues:

The pardon power—almost absolute on its face where it appears in Article II, Section 2—makes for some easy illustrations of just how essential it is for Congress to be able to examine presidential intent or motive in an impeachment case involving what might otherwise look like a facially valid exercise of executive power. Imagine the president pardoned [Arizona sheriff Joe] Arpaio in exchange for $1 million in cash. Could Trump be impeached for the pardon? Of course—this is bribery, and Congress has been vested with the power to impeach and remove him for it. Imagine the president granted a set of pardons to assist a foreign adversary in waging war against the United States. Could he be impeached for the pardons? Of course—this is treason, and Congress has been vested with the power to impeach and remove him for it. Imagine the president were to “announce and follow a policy of granting full pardons, in advance of indictment or trial, to all federal agents or police who killed anybody in line of duty, in the District of Columbia, whatever the circumstances and however unnecessary the killing.” Could he be impeached for his pardon policy?

The more ferociously Republicans advance the argument that Trump can essentially say and do whatever he deems fit with regard to the investigation and the Justice Department as a whole, the more they will box themselves into a position of denying that grounds for impeachment exist no matter what the special prosecutor finds. And perhaps that’s the point — to discredit the power of impeachment altogether. More independent-minded Republicans, Democrats, political independents, the organized legal community and former Justice Department officials from both parties should strenuously push back on that effort — lest they be seen as enabling further attacks on the rule of law and inducing a constitutional crisis in which grave violations of the DOJ’s autonomy and the pardon power are committed.