Robert Mueller’s report makes the stirring claim that “a fundamental principle of our government” is that no person, not even the president, “is above the law.”

But the special counsel’s ultimate legacy may well be the exact opposite — because of his controversial decision not to say whether Trump committed criminal obstruction of justice.

“We concluded that we would not reach a determination, one way or the other, about whether the president committed a crime,” Mueller said in his statement Wednesday, reiterating his report’s explanation.

It was the punt heard around the world. It may have been the crucial turning point in the saga of the special counsel probe, and perhaps the decision most likely to have ramifications for future presidents. It effectively “removes the president from the scope of generally applicable criminal laws,” Cornell law professor Jens David Ohlin recently told my colleague Sean Illing.

Essentially, Mueller has laid out a model that federal prosecutors can investigate the sitting president for crimes, but that they should not make any conclusion about whether he committed a crime. In a sense, this does seem to place the president above the law.

To be clear — this was Mueller’s own choice. Yes, he did conclude that existing department policy prevented him from indicting a sitting president. But before the special counsel wrapped up his work, it was widely believed that he might still issue a judgment on whether Trump committed a crime.

He did not do so, and this “took some constitutional scholars and Justice Department veterans by surprise,” the Washington Post’s Rosalind Helderman wrote Wednesday. Helderman quotes J. Michael Luttig, a former appellate judge and former Justice Department official, saying: “The fact that a president cannot be prosecuted does not foreclose a finding by a special counsel of whether a president committed a crime.”

Oddly, Mueller also went out of his way, both in his report and his statement, to opine that he did not have “confidence” that Trump didn’t break the law. And his legal analyses of certain incidents involving Trump sure seem to suggest he violated the law. But he refused to take the final step and outright come to a conclusion — something Attorney General William Barr has repeatedly said he expected the special counsel to do.

Mueller was also careful never to say that he couldn’t have issued a criminal finding about Trump. In the report, he writes several times that his office “determined” not to do this, and in his Wednesday statement he used the word “concluded.” Additionally, Barr proceeded to ignore this considered decision not to decide, quickly issuing his own conclusion that, in his view, Trump didn’t violate the law.

Still, Mueller’s decision-making around the highest-profile criminal investigation into a president in decades is unmistakably important, and could be viewed as a model for similar future investigations to follow. So we deserve more transparency about how it came about.

Mueller’s reasoning for choosing not to say whether President Trump broke the law

For a report that’s 448 pages long, Mueller’s decision to end his investigation of Trump with a punt is somewhat under-explained.

The special counsel lays it out quickly in the introduction of his report’s second volume. First, he writes, he “accepted” the Justice Department Office of Legal Counsel’s 2000 opinion that the department can’t indict a sitting president because it would undermine his capacity to carry out the work of the executive branch. Second, the report continues, the office determined that investigating the president “is permissible” anyway, to preserve evidence, and because the president wouldn’t have immunity from indictment after he leaves office. So far, that’s all as expected.

But then comes the punt. Though the office “considered” whether to evaluate Trump’s conduct under Justice Department standards about prosecution decisions, Mueller writes, it “determined not to apply an approach that could potentially result in a judgment that the President committed crimes.”

And his main reason is a curious one — that it would be unfair to the president, because the fact that he can’t be charged means he can’t clear his name with an acquittal at trial.

Fairness concerns counseled against potentially reaching that judgment when no charges can be brought. The ordinary means for an individual to respond to an accusation is through a speedy and public trial, with all the procedural protections that surround a criminal case. An individual who believes he was wrongly accused can use that process to seek to clear his name. In contrast, a prosecutor’s judgment that crimes were committed, but that no charges will be brought, offers no such adversarial opportunity for public name-clearing before an impartial adjudicator.

Mueller reiterated this point in his statement Wednesday. “Beyond department policy, we were guided by principles of fairness,” he said. “It would be unfair to potentially accuse somebody of a crime when there can be no court resolution of an actual charge.” In the report, he refers to this as the “absence of a neutral adjudicatory forum” to review the report’s findings.

Mueller expresses another concern in the report as well — namely, that finding the president committed a crime in an internal report “could carry consequences that extend beyond the realm of criminal justice.” Specifically, it could “imperil the President’s ability to govern.”

So, Mueller said in his statement: “We concluded that we would not reach a determination — one way or the other — about whether the president committed a crime. That is the office’s final position.”

Mueller’s move sets a worrying precedent

Even though Mueller made clear this was his own decision, it will inevitably set a precedent for future investigations into presidents — a problematic one.

If Mueller’s approach is taken as a model, the Justice Department can investigate to their heart’s content, but at the end of the day, they not only won’t indict a sitting president, but they won’t even say whether he broke the law.

It’s the very definition of special treatment, and would essentially remove one potential check on presidential wrongdoing from within the executive branch. It would mean the department charged with investigating and charging violations of federal law won’t assess whether one particular person, the president, violated federal law.

Mueller’s concern about “fairness” to the president, who would lack a forum to clear his name after being accused, is particularly odd.

“That is completely absurd,” Ohlin, the law professor, told Illing. “The president doesn’t have a courtroom to vindicate his innocence only because the DOJ has decided that his office makes him immune from indictment in the first place. It’s a piece of circular reasoning that removes the president from the scope of generally applicable criminal laws.”

The special counsel appears to realize the implications of this position, so in an apparent attempt to mitigate it, he does offer an opinion on Trump’s conduct — that it’s, well, not obviously innocent.

“If we had confidence after a thorough investigation of the facts that the President clearly did not commit obstruction of justice, we would so state,” Mueller writes in his report’s final paragraph.

Indeed, many who have read the report closely have remarked that its legal analysis often seems quite damning for Trump. Lawfare’s Quinta Jurecic, for example, parsed the report’s language about several examples of Trump’s potentially obstructive conduct, with an eye toward whether it established all three legal elements of criminal obstruction of justice. For four examples, the report seems to do just that. Hundreds of federal prosecutors have also opined that Trump’s conduct as outlined in the report would merit charges if he wasn’t president.

But in the end, Mueller, the person who was charged with investigating whether the president of the United States violated the law, refused to outright make a judgment on whether he did. And if, in the future, Justice Department investigators are looking into a sitting president’s potentially criminal conduct, they might feel obligated to follow his example and do the same, rather than rocking the boat.

This wasn’t the obvious call — and Barr quickly made a different call

Again, Mueller did not conclude that he was prohibited from making a criminal finding about the president. He says he “considered” doing so. It’s just that he concluded that he wouldn’t.

This was far from a foregone conclusion, it certainly came as a surprise to me and others who have covered Mueller’s investigation for years.

Attorney General William Barr, for instance, testified that he was “frankly surprised” to learn this in March and that he “did not understand exactly why the special counsel was not reaching a decision.”

Indeed, Barr proceeded to do exactly what Mueller wouldn’t — evaluating the evidence and concluding that, in his view, it wasn’t sufficient to establish Trump committed a crime. So, in a sense, Mueller’s considered decision not to decide was immediately thrown out the window by his superior.

“The opinion says you cannot indict a president while he is in office,” Barr told CBS News this week. “But he could’ve reached a decision as to whether it was criminal activity.”

Mueller may have had other reasons for restraint

Perhaps hanging over all this is the fact that, if Mueller had submitted a report to Barr concluding that Trump committed a crime, it would have initiated a crisis.

Mueller would have been the man who threw the Justice Department into turmoil, as the department would inevitably have struggled with how to handle such an explosive conclusion. (Remember that Barr was not legally obligated to make Mueller’s findings public.)

Once the news inevitably got out, Mueller would likely have become the man who lit the impeachment fuse. Congressional Democratic leaders are having enough difficulty holding off their base’s desire to impeach Trump as it is. An unambiguous conclusion from Mueller that Trump violated the law would have led to pressure that may well have been impossible for them to withstand.

It’s possible Mueller believes that’s a decision that should be made by Congress, not a Justice Department prosecutor. The House of Representatives is essentially the “prosecutor” in the impeachment process — they can vote to kick-start a trial in the Senate. He might have envisioned his job as limited to gathering evidence and presenting some analysis.

But when Mueller’s report does reference impeachment, he seems concerned about interfering with that process. A “criminal accusation against a sitting President,” he writes, could “potentially preempt constitutional processes for addressing presidential misconduct.” (A footnote there makes clear he means impeachment). So essentially, Mueller has ceded the role of deciding whether the president committed a crime to Congress.

There may also have been features of the case itself that made Mueller prefer restraint. He didn’t establish an underlying conspiracy between the Trump campaign and the Russian government to interfere with the election. And despite all his troubling obstruction evidence, he lacked an indisputable smoking gun example, like Trump outright telling witnesses to lie to investigators or destroying evidence.

But his decision really deserves more transparency and debate

In the end, Mueller’s decision not to make a criminal finding one way or the other may be the most crucial decision he made during his investigation — and we should really get more transparency about it.

When did the special counsel decide on this approach, exactly? What was the debate over it like? How close was he to going in a different direction? What sort of internal analyses were written on this topic? Was his decision based on the particular circumstances of this case, or would his reasoning apply to all similar investigations? Should the new standard be that the Justice Department never opines on whether the president has violated the law?

It’s understandable that Mueller doesn’t want to testify before Congress about uncharged individuals and uncharged conduct, as per Justice Department practice. But this is a process call that could have major consequences for future investigations of presidents, and accordingly deserves a good deal more review and debate.

Considering how consequential this decision may have been, the few paragraphs about this in Mueller’s report simply aren’t enough — nor are his brief remarks this week. His decision poses the risk that future investigations of presidents will be hamstrung from the start. So he should give a better explanation of why he made this call.