Senate Majority Leader Mitch McConnell recently addressed the Mueller investigation on the Senate floor declaring, “Case closed.” He made it clear that, in his eyes, the Mueller Report completely cleared the president and his campaign of conspiracy or cooperation with the Russian efforts to interfere with the 2016 elections, while making no mention of the obstruction accusations in Volume II of the report. In effect, McConnell’s rhetorical sleight of hand was a shameful act of political posturing unbecoming any senator, much less the majority leader.

Every senator swears an oath “to support and defend the Constitution of the United States” and to “bear true faith and allegiance to the same.” They swear no oath to a political party, which exists to facilitate cooperation among like-minded voters and politicians but not to command loyalty.

As James Madison wrote in Federalist 51, “In republican government, the legislative authority necessarily predominates.” Congress, as the branch closest to the people and most subject to their will, has more checks over the other branches than they have over it. With that power comes the responsibility to oversee the other branches, ensuring their operations are efficient, lawful, and fair.

The Mueller Report is nothing if not a litany of abuses in the executive branch, in which the president and those around him used their powers unfairly, perhaps illegally, and certainly in their own interests against and above those of the American people. Sen. McConnell has a duty to investigate and correct those abuses, but instead, “Case closed.”

There is a charitable explanation of McConnell’s speech: Perhaps his silence on obstruction charges indicated that, with respect to presidential misconduct writ large, case open. But McConnell’s effect is to shield the president under the umbrella of his studied silence.

Moreover, Sen. McConnell’s elision of the credible accusations against the president and his administration will weaken the Republican Party in the long term. He has ceded the cause of accountable government to House Democrats, who will embrace their responsibility now but will likely cast it off when it no longer suits them. If Republicans don’t believe in accountable government and close oversight now, they’ll have no credibility when they claim to believe in it under a President Biden, Sanders, or Harris.

Moreover, the purpose of the Republican Party and the conservative movement has been to keep the government small, transparent, and accountable to the voters and the Rule of Law. Is it worth throwing away decades of achievement to win a news cycle?

Sen. McConnell is wrong. The case is not closed. The American people, the source of all legitimate political power, will have their answers – through the House if they must, or with the participation of the Senate if they can. Sen. McConnell can choose to continue to stand athwart his principles, or he can embrace his duty as a Senator, and a party leader.

Future writers of history are watching closely.