Jim Bourg / Reuters

One must assume that the primary purpose of Special Counsel Robert Mueller’s surprise Wednesday press conference was the clarification of what he considered to be widely held misconceptions about his report. Alas, by the time Mueller had finished speaking, Americans seemed more confused than ever. Now, as before, to ask what Mueller “really meant”—and, indeed, what he “really thinks”—is to receive 100 different answers. The Mueller report, as the cliché goes, has ended up as a Rorschach test.

Americans will hear all sorts of explanations as to why this is. We will be told that it is because we are too “divided,” or because we live in a “post-truth world,” or because Attorney General William Barr is too sneaky. But none of these explanations is correct. The truth is that from the very moment the investigation was announced, it was inevitable that we would end up with a mess. Because, as usual, our political leaders abdicated their constitutional responsibilities and contrived to use the wrong tools for the job.

Having apparently learned nothing from the failure of the now-expired Independent Counsel Act, Washington D.C. settled quickly on the idea that the best way to examine whether the head of the executive branch had done something criminal was to open an investigation within … the executive branch. That this approach was absurd would have been clear in any other circumstance; can we really imagine permitting the subject of, say, a racketeering investigation to control his investigator on the understanding that any improprieties would be evaluated later? For some reason, though, when the president is involved, we tell ourselves that if we just get the right guy, everything will work out.

It didn’t. And it can’t. This is not, I must stress, because Mueller is a bad person. On the contrary: Mueller seems to be a man of integrity. Rather, it is because to ask the executive branch to investigate itself is to make demands of the American constitutional order that the American constitutional order cannot support.

There were only two possible outcomes here. The first of those outcomes was that President Donald Trump left Mueller’s investigation alone completely and did not retain even a cursory oversight role. This, clearly, was an approach that many hoped to see Trump take. I cannot count the number of times I heard it said that Mueller must be permitted to retain his “independence.” But for Trump to have done this would, in effect, to have been to create a de facto fourth branch of government that was ultimately accountable to nobody. The prosecution power is vested in the executive branch. Trump is the head of the executive branch. An investigation conducted without his superintendence would have been, by definition, illegitimate.

The other potential outcome—the one we got—was that Trump maintained the authority over his branch that the Constitution accords him, and was chastised for having done so. One does not need to believe that Trump’s conduct was irreproachable to grasp that the charges of “obstruction” on which we are all now focused were unavoidable by dint of the way the investigation was set up. Criminal obstruction, remember, hinges not on action but intent. Because he is the head of the executive branch, Trump enjoys a wide latitude to direct the Department of Justice. Determining whether he used that power for good or for ill is, ultimately, a matter of judgment—of mind reading, even. There is no detective in the world who can do that job. There is probably no detective who should.

Advocates of the Mueller investigation maintain that, as president, Trump should have behaved in a more sober way, and thereby allayed fears that he was trying to cover something up. And, indeed, as a matter of political propriety, he should have done just that. But as the Founders understood, to predicate your political system on the demand that men with power “should behave better” is to set yourself up for failure. Experience has taught us that kings do not relinquish their authority to please the chattering classes, and that self-interest and ambition cannot be quelled by chastisement or persuasion. Only a rival power center can do that.

I am talking, of course, about Congress, which is supposed to be at the center of our federal politics, but which has in recent years rendered itself depressingly otiose. Congress, lest we forget, is far and away the most powerful of the three federal branches—so powerful, in fact, that it can remove pretty much every single person within the others for reasons of its own invention. Had it done its job and led the investigation into Trump, it would have likely avoided all the intractable problems that the Mueller investigation introduced.

Because Congress is a separate branch, there would have been no conflicts of interest between the investigator and the investigatee­, and, in consequence, there would have been no muddy charges of “obstruction”; either the president would have complied or not. Rather than confusing everyone in an attempt to set up a mythical “fourth branch,” the political lines would have been clear for the public to judge—an important feature in any democratic system. And, perhaps most important of all, there would have been no restrictions on what the investigation could have legally accomplished. Had he so desired, Mueller would have been unable to bring charges without falling afoul of Office of Legal Counsel rules and raising some difficult constitutional questions (can the president arrest himself?). Congress, by contrast, is able to impeach the president for whatever reason it likes, whenever it likes, and without any need for outside permission.

We have just been through a two-year saga in which the executive branch conducted a criminal investigation into whether the executive branch was guilty of criminal conspiracy, and concluded that while there was no evidence that the executive branch was guilty of criminal conspiracy, there was some evidence that the executive branch tried to obstruct the executive branch’s investigation into an offense that didn’t happen—evidence that led a prosecutor whose job is not to pronounce guilt or innocence to publicly announce a verdict of “not exonerated.”

Ensuring that this does not happen again—and make no mistake, we will investigate another president—will be extremely difficult. Members of Congress have become accustomed to taking the back seat, and, because doing so permits them to duck difficult votes, even seem to prefer it that way. Partisanship has rotted away the harsh rivalry between the branches and replaced it with hypocrisy; now oversight is wholly contingent upon which parties run which institutions at any given point. And the public, which is generally ambivalent about politics and politicians, has decided that the only real drama worth watching is that of the White House. But that it will be hard is no reason to shirk the effort to make Congress great again. America’s system works when it is used as designed. The Mueller investigation was an attempt to perform an end run around that system. His team never had a chance. We didn’t either.

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