...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 which “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.