President Trump, the New York Times was the first to report Thursday night, tried to fire special counsel Robert S. Mueller III last summer, only to be thwarted by White House Counsel Don McGahn, who threatened to quit if the president went through with it. That episode may well have marked the beginning of a broader softening toward Mueller’s investigation, as reflected in the less antagonistic stance the Trump administration has been taking toward the special counsel in recent weeks.

But we shouldn’t have to depend on McGahn to ensure that Trump honors the rule of law. Instead, the latest news shows why it’s so urgent for Congress to act to protect Mueller — and to ensure that he can only be fired for good cause.

Under the 1999 federal regulation pursuant to which Mueller was appointed, a special counsel can be fired only “for misconduct, dereliction of duty, incapacity, conflict of interest, or for other good cause.” But whether the circumstances of a particular case give rise to such malfeasance is to be determined by the attorney general (or, because Attorney General Jeff Sessions recused himself from this case, Deputy Attorney General Rod J. Rosenstein). The regulations have no obvious mechanism for the special counsel to challenge termination he believes to be wrongful in court. Thus, even if the president did not actually have good cause to order Mueller’s firing, the deputy attorney general could do it anyway — without having to worry about that decision being reviewed by a judge.

To protect against this very possibility, two bills were introduced last year in the House and Senate — the Special Counsel Independence Protection Act and the Special Counsel Integrity Act. Although they differ in some of their particulars, both have at their core a relatively straightforward idea: If a special counsel is fired and disputes the reasons for his termination, he can challenge them in court. Independent federal judges, rather than senior political appointees in the Justice Department, would get the last word on whether good cause for firing the special counsel did, in fact, exist.

Opinion | If President Trump fires the bane of his legal troubles, he could spark a legal and constitutional crisis. (Adriana Usero/The Washington Post)

The bills don’t change the procedural or substantive rules governing the special counsel’s authority, or the grounds on which he can be fired; they simply ensure a role for the courts in reviewing any dismissal to make sure it’s done for the right reasons and not the wrong ones. Indeed, the modesty of the bills is why, as University of Chicago law professor Eric Posner and I testified at a Senate Judiciary Committee hearing on the draft legislation in September, they don’t raise any serious constitutional concerns (especially while the Supreme Court’s 1988 decision upholding the independent counsel statute remains on the books). It may also be why these bills not only have bipartisan support, but why the Senate versions are co-sponsored by Sens. Lindsey O. Graham (R-S.C.) and Thom Tillis (R-N.C.), respectively — hardly the most ardent critics of Trump within the Republican caucus. Graham, in fact, has been one of Trump’s most loyal defenders recently, even though his name is on the legislation designed to be a fail-safe protection from the president’s impulses.

In any other Congress, one might have expected these bills to have passed easily and without much notice. But since its September hearing on the legislation, the Senate Judiciary Committee has sat on them, and the bills do not appear to be any further along in the House. Why progress has stalled seems fairly obvious: It’s easy to support legislation at the drafting and hearing stage, but it takes a real commitment to the bills — and the expenditure of precious political capital — by senior Republicans in both the House and the Senate to get them to a floor vote. At least until Thursday night, there may have appeared to be no compelling reason to expend that capital. Trump had mostly stopped publicly attacking Mueller, after all, so the specter that he’d fire him wrongfully may have looked to some like more of a boogeyman than a legitimate, pressing concern.

But now the idea of the president, in a moment of unmoderated anger, ordering Mueller’s termination seems quite real — since, as the Times reported (and others, including The Washington Post, confirmed), it’s already happened. And the next time Trump has the same impulse, there’s no guarantee that he’ll again be thwarted by his own staff.

So the question every member of Congress ought to be asking (and be asked) is whether they recognize the urgent need to protect Mueller from Trump’s irrational wrath. If Mueller is going to be fired, it must be for reasons that can stand up to at least minimal judicial scrutiny. And if Republicans in Congress are serious about allowing Mueller’s investigation to go forward, preventing Mueller’s removal without a judicial finding of good cause would be a relatively low-cost means of carrying through on their rhetoric and showing Trump that these are more than just empty platitudes. Otherwise, we’re left to rely on political appointees such as McGahn — until and unless they, too, are fired.

CORRECTION: An earlier version of this story misidentified the state Sen. Thom Tillis represents. He is from North Carolina, not Illinois.

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