Aaron Bernstein / Reuters

In today’s blockbuster hearings, Senate Judiciary Committee members cross-examined Attorney General William Barr on his short March 24 letter summarizing Special Counsel Robert Mueller’s probe. In that letter, Barr stated that Mueller had declined to reach a judgment on whether Donald Trump had obstructed justice. Senate Democrats seized on a letter by Mueller complaining that Barr’s short report to Congress “did not fully capture the context, nature, and substance of this office’s work and conclusions” and therefore threatened to “undermine a central purpose” of the special counsel: to ensure “full public confidence in the outcome of the investigations.”

Criticism of Barr’s summary makes much ado about nothing. Barr released the Mueller report just a few weeks later, with the crucial second volume on obstruction of justice virtually unredacted. Members of Congress and the public can reach their own judgments now on the Mueller report’s findings on obstruction. How Barr characterized Mueller’s findings makes no difference.

But fixating on who wrote and said what about someone’s characterization of someone else’s report deflects attention from the most important thing about Barr’s letter: The attorney general did not just summarize Mueller’s conclusions; he also filled the gap left by Mueller’s refusal to decide on obstruction. “The evidence developed during the Special Counsel’s investigation is not sufficient to establish that the President committed an obstruction-of-justice offense,” Barr concluded in his letter. He and Rod Rosenstein, then the deputy attorney general, reached this view “without regard to, and … not based on, the constitutional considerations that surround the indictment and criminal prosecution of a sitting president.”

Yet Barr’s decision should have come as little surprise. Last June, well before his appointment as attorney general, Barr sent an unsolicited memorandum to the Justice Department arguing that Mueller’s obstruction investigation was “fatally misconceived.” He argued that a president could not commit obstruction by exercising his constitutional powers, such as his sole authority to remove the FBI director, or even by terminating a criminal prosecution. To allow Mueller to proceed, Barr argued, “would have grave consequences far beyond the immediate confines of this case and would do lasting damage to the Presidency and to the administration of law within the Executive branch.” Barr repeated that view today: “The president does not have to sit there constitutionally and allow it to run its course,” he told senators. “The president could terminate the proceeding, and it would not be a corrupt intent, because he was being falsely accused.”

Yesterday’s hearings began to make clear that Barr thought Mueller should not have even investigated Trump for obstruction. As his report indicated, Mueller believed himself bound by a Clinton Justice Department’s 2000 ruling that “the indictment or criminal prosecution of a sitting President would impermissibly undermine the capacity of the executive branch to perform its constitutionally assigned functions.” But if the Justice Department cannot indict a sitting president, as Barr observed, Mueller should not have continued a probe that could have no fruitful end.

Barr, however, misunderstands Mueller. Mueller looked into 10 episodes, almost all of which did not involve normal obstruction such as witness intimidation or evidence tampering. Instead, Trump’s actions, such as firing James Comey, his order to remove Mueller (thankfully ignored), or another command to shut down the special counsel’s investigation (ditto), could have represented the president’s good-faith exercise of his constitutional duty to “take care that the laws be faithfully executed.”

Mueller could not find the crucial element of obstruction, which is that the president held a “corrupt” mental state to interfere with a legitimate legal proceeding. This is a delicate judgment, because some acts that appear legal can become obstruction, depending on the motive. Sending money to a witness’s family, for example, does not violate any law, unless a mob boss does it to buy the witness’s silence. Mueller could not reach a judgment that Trump had that corrupt motive without interviewing Trump directly. Here, the president’s lawyers outfoxed Mueller by refusing to make Trump available for live testimony and by barring any written questions on obstruction.

But critics wrongly challenge Barr’s and Mueller’s declination to prosecute. Instead, they should welcome it. Their decisions return the duty to curb presidential abuses of power to its constitutional seat—Congress. Mueller makes clear that he “conducted a thorough factual investigation in order to preserve the evidence when memories were fresh and documentary materials were available,” even though he could not prosecute a sitting president. Why? The reason Justice does not prosecute sitting presidents, Mueller argues, is so as not to “potentially preempt constitutional processes for addressing presidential misconduct.” The only mechanism that the Framers established to remedy presidential abuse of power remains impeachment.

Impeachment must be the only solution to Trump’s challenge to the constitutional order. The Constitution did not envision that the criminal-justice system would address abuses of presidential power. Since Watergate, we have embarked on a 40-year experiment in using the criminal law to resolve separation-of-powers disputes. If Ken Starr’s sprawling Whitewater probe had not already demonstrated it, the Mueller report should prove that the experiment has failed. The Framers vested in the president the authority to oversee all federal law enforcement. As Alexander Hamilton observed in “Federalist No. 70,” “good government” requires “energy in the executive,” and a vigorous president is “essential to the protection of the community from foreign attacks” and “the steady administration of the laws.” Because of this original design, a president can order the end of any investigation, even one into his own White House.

The creation of independent counsels was an attempt to solve this conflict of interest, but the cure was worse than the disease. A special counsel, as even Trump realized upon learning of Mueller’s appointment, could spell the end of a presidency by diverting executive power outside constitutional controls and sapping the White House of its energy. Independent counsels further have the convenient effect of relieving Congress of its own constitutional duty to constrain an abusive president.

If Congress truly believes that a president has abused his powers, it can cut off funds, block his nominees, and impede his legislative priorities. It can proceed under impeachment, which allows for the removal of a president for treason, bribery, “or other high Crimes and Misdemeanors.” As Hamilton explained in “Federalist No. 65,” this last category of offenses includes those that “proceed from the misconduct of public men, or, in other words, from the abuse or violation of some public trust. They are of a nature which may with peculiar propriety be denominated political, as they relate chiefly to injuries done immediately to the society itself.” Congress can conclude that the same conduct raised in the Mueller report justifies removal from office, even if it is not criminal.

The Framers did not want legislators to avoid the responsibility of curbing presidential abuse of power by hiding behind prosecutors or the courts. Impeachment may place that awesome duty in a body subject to political pressures and sensitive to other national demands. Nevertheless, the Constitution makes Congress alone accountable for removing a president who abuses his office. Ultimately, both Attorney General Barr and Special Counsel Mueller have done the nation a service not just by clearing the president of collusion, but by returning the question of obstruction to Congress, where it belongs.

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