Volume Two of the Mueller report, which focuses on evidence of obstruction of justice, is more complicated than volume one, and even more damaging to the White House. It is a familiar takeaway from Watergate that it was not the crime but the cover-up that ultimately brought down the Nixon presidency. Volume Two of the Mueller report is all about the cover-up. In his initial letter to Congress summarizing the Mueller report, Attorney General William Barr concluded that if there was no underlying crime to be hidden, then the cover-up itself was not worthy of criminal prosecution. If there was no collusion – or at least, no criminal conspiracy – then there could be no obstruction of justice in trying to derail the investigation of the potential collusion. A dose of technicality and a shot of mercy are enough to get the president off the hook of criminal charges, at least according to Barr.

Much has been made of the tensions between the Mueller report and Barr’s initial summary of that report. Certainly the tone of the two documents is rather different. But Barr’s bottom line on the conclusion of the obstruction-of-justice investigation was at least consistent with the Mueller report. Mueller declined either to “conclude that the President committed a crime” or to “exonerate him.” Barr did not claim to exonerate the president either. Rather, the attorney general concluded that in his prosecutorial judgment, the president’s actions were unlikely “to be proven beyond a reasonable doubt” to constitute obstruction of justice. That is, to be sure, a contestable judgment, but it is not an unreasonable one.

The Mueller report did not lay out a slam dunk case of obstruction of justice, but it did lay out a plausible case. A prosecutor might reasonably decide that a merely plausible criminal case should not be brought to court. Perhaps the president enjoyed a home court advantage as his attorney general deliberated on the case, but that would hardly be surprising.  Perhaps a different prosecutor would have been more aggressive, more willing to assume the risk of going forward with a shaky case, more willing to roll the dice on persuading a jury and winning a long battle in the appellate courts, but that is why we recognize the concept of prosecutorial discretion. Barr’s judgment is certainly open to criticism, but that does not mean that he has acted unprofessionally.

Barr rested his conclusion not to prosecute on the factual and legal vulnerabilities of the obstruction case. Those vulnerabilities are real. The president might have been keen to impede the Russia investigation, but he was not particularly effective in doing so. Many of his acts that might be understood to interfere with the investigation took place in public view and involved his constitutionally derived powers and could plausibly be explained as being, at least in part, motivated by public-regarding reasons. If the president believed that the Russia investigation was, in fact, a politically motivated witch-hunt that was hampering his administration’s ability to get on with the business of advancing the people’s interests, then his efforts to foreshorten that investigation through the use of his lawful powers might have been ill-advised but well-intentioned. The fact that the investigation did eventually come to a proper conclusion and did not recommend criminal charges of conspiracy might be seen as justifying the president’s frustrations with it and mitigating his culpability for expressing and acting on those frustrations. Others might be less sympathetic with the president’s dilemma and less forgiving of how he responded to the situation, but Barr might reasonably think that the case was a hard one and in such circumstances a prosecutor should not be eager to put a sitting president in the dock.

Hovering in the background, however, are some significant constitutional disagreements between Barr and Mueller that have a bearing on the strength of the obstruction case laid out by the special counsel. In a letter last year to the Trump administration, then-former Attorney General William Barr argued that applying the federal obstruction statutes to facially valid uses of the president’s constitutional powers raised grave constitutional difficulties. Given those concerns, Congress should not have been understood to have intended such an application of the statute. But even if Congress did mean for the obstruction statute to have such a sweeping application, it should not be applied that way because doing so would necessarily interfere with the core constitutional functions of the chief executive. If prosecutors and courts were allowed to second-guess the private motives behind presidential decisions about how to exercise such discretionary executive powers as removing executive officers, launching prosecutions, or issuing pardons, then presidents would be open to endless political harassment and would effectively be subject to judicial control in their political and policy decision-making. Ever since Marbury v. Madison, the Court had recognized that judges could not interfere with how the president exercised his discretionary constitutional authority. Barr believes that applying the obstruction statutes to otherwise lawful uses of executive power would do just that.

Special counsel Robert Mueller sketched out a very different understanding of the constitutional authority of the president and its relationship to the judiciary. Mueller emphasized that the courts have adopted a balancing test when assessing statutory interference with presidential powers that are merely implied by the constitutional text. When the president exercises the power of removing executive officers, for example, he relies on an inference from the constitutional structure rather than a specific textual delegation of power. In such cases, the courts might find that some particularly powerful congressional interest is sufficient to override the otherwise absolute discretion that the president might enjoy. The desire to prevent the president from corruptly subverting justice might provide just such a rationale to circumscribe presidential discretion. Moreover, by limiting the president only to the degree that he seeks to use his powers for corrupt ends, Congress is enhancing rather than interfering with the president’s constitutional duty to take care that the laws be faithfully executed. If corrupt uses of presidential power are never properly part of the president’s Article II constitutional authority in the first place, then it does no great damage to the presidency to make that limit explicit and judicially enforceable.

Mueller would underscore that substantial and credible obstruction-of-justice charges against the president would be exceedingly rare. As a consequence, he believes that no normal president should have any concern about the possibility of such charges being filed or of a court reviewing them. Barr is not so sanguine. Barr more easily imagines a world of partisan warfare in which the attempted criminalization of presidential decisions will be all too common and presidents will necessarily have to anticipate judicial scrutiny of their actions and hedge accordingly. Presidents Bill Clinton and Donald Trump might commiserate together over the consequences for their administrations of having lawyers poring over their every move.

At the end of the day, Mueller took a somewhat cautious approach to the obstruction-of-justice issues surrounding the president. That cautious approach was justified. Mueller was not in the position of a junior prosecutor making a private recommendation to his superior about whether to pursue criminal charges against an ordinary individual. He was preparing a public document regarding potential criminal charges against the president of the United States for an attorney general who had already expressed deep skepticism about the appropriateness of such charges. Moreover, he was doing so in a context in which he felt bound by existing Department of Justice guidelines holding that a sitting president could not even be indicted, let alone prosecuted in a criminal court. In such circumstances, some modesty is appropriate.

Both Mueller and Barr disclaimed any direct reliance on the earlier opinions shielding a sitting president from criminal indictment, but the rationales offered by the Office of Legal Counsel in those opinions are in alignment with Mueller’s cautious approach of not reaching a conclusion on the obstruction-of-justice charges. The OLC has emphasized that the constitutional text specifies impeachment as the appropriate mechanism for addressing wrongdoing by a sitting president, that only Congress and not an individual prosecutor and grand jury should assume the responsibility of interfering with the president’s ability to conduct his office by forcing him to attend to a legal defense, and that a criminal indictment would put the president under such a shadow of “stigma and suspicion” that it would in and of itself politically debilitate the president as a national and international leader.

If presidential immunity from indictment flows from such considerations, then a public announcement by a prosecutor that a president should be indicted should be constitutionally disfavored as well. During the Nixon administration, the Justice Department concluded that the “spectacle of an indicted President still trying to serve as Chief Executive boggles the imagination.” The spectacle of a president trying to serve as chief executive after a special counsel has formally and publicly announced that the president has committed serious criminal offenses is no easier to imagine. An indictment would effectively force Congress’s hand on the decision of whether to impeach and remove the president. A Justice Department recommendation that the president be criminally prosecuted would do the same. Mueller and Barr left the House with discretion over whether or not to act. If the OLC was right to conclude that a sitting president should not be subject to indictment, then Mueller was also right to conclude that he could only exonerate but never condemn the president.

There is a also substantial gap between what is required to exonerate someone of potential criminal offenses and what is required to prove their guilt beyond a reasonable doubt. Mueller might reasonably believe that he was operating within that gap. He did not face a binary choice between exoneration and condemnation. He had a third option that fell somewhere in between. If he found himself in that murkier zone of twilight, then simply laying out his factual findings and the relevant legal considerations might well have been the best option.

Mueller left it to others to draw their own conclusions about the nature and severity of the president’s offenses. The president might not be criminally liable, but his actions were foolhardy, contemptible, and beneath the dignity of his office. The president showed himself to be without political or constitutional judgment. He behaved irresponsibly. The Mueller report provides yet more evidence that the president’s instincts are deeply authoritarian, lawless, and selfish. Time and time again, the president was saved by his subordinates from making even more egregious errors. The members of Congress, in exercising their constitutional responsibilities, and the voters, in exercising their franchise, are best positioned to hold the president accountable for his actions.

After the president fired James Comey, I wrote that in order “to get out of impeachment territory” the administration should “welcome the appointment of a special counsel and ramped-up congressional inquiries and declare its confidence that the air will soon be cleared with its full cooperation.” Instead, the president stonewalled any and all investigations, publicly and privately raged against the investigators, and at least contemplated bringing all investigations to a screeching halt by removing both the attorney general and the special counsel. If the administration had acted on the president’s desires, his impeachment and removal would have been amply warranted.

As it stands, the case for impeachment is less clear but far stronger than it would have been had the president only listened to the advice of such politically savvy lawyers as White House counsel Don McGahn and former governor and federal prosecutor Chris Christie. In essence, the president must now rest his case on the claim that he merely wanted to, but did not, commit impeachable offenses, that his administration has proven to have adequate guardrails to contain the president’s own reckless inclinations, and that the Russia investigation that so bedeviled the president is now in the past and so both he and the country can move on to grapple with issues that are less likely to so inflame the president’s passions and provoke him to constitutionally dangerous behavior. That this is the best rationale for allowing the sitting president to serve out his remaining term of office is hardly reassuring.

Photo: Gage Skidmore from Peoria, AZ, United States of America [CC BY-SA 2.0 (https://creativecommons.org/licenses/by-sa/2.0)]

Keith E. Whittington is the William Nelson Cromwell Professor of Politics at Princeton University and the author of the forthcoming book, Constitutional Crises, Real and Imagined.