Since 1973, I have been a professor of constitutional law. The Supreme Court is at the very center of my professional life. I served as a law clerk to Justice William J. Brennan, Jr.; I am co-author of one of the nation’s leading constitutional law textbooks; I am an editor of the Supreme Court Review; I have written numerous books and scholarly articles on the Supreme Court; I am editor of a 20-volume series titled Inalienable Rights, which focuses on the meaning of our constitutional rights; and I have taught courses on constitutional law to generations of law students.

Throughout my career, I have honored the fundamental role the Supreme Court plays in our system of government. There have, of course, been many Supreme Court decisions with which I’ve disagreed over the years, but I have always respected the essential legitimacy and integrity of the Supreme Court as an indispensable institution in our American democracy.

But now, for the first time in my career, I find myself hesitating. This is not a reflection on the judgment or integrity of any of the current or former justices. It is, rather, a reflection on what the Senate Republicans have done to the fundamental legitimacy of the Supreme Court in the future. By refusing to confirm President Barack Obama’s appointment of Chief Judge Merrick Garland to the Supreme Court, Senators Mitch McConnell, Charles Grassley, and their Republican cronies betrayed our constitutional traditions and undermined a central principle of American democracy. Although they maintained that their unconscionable behavior was “justified” by the fact that the vacancy arose during President Obama’s final year in office, this was a blatantly dishonest assertion. In fact, a long line of presidents have made appointments to the Supreme Court in the final year of their terms, including such historic figures as George Washington, Thomas Jefferson, Andrew Jackson, Abraham Lincoln, William Howard Taft, Woodrow Wilson, Herbert Hoover, Franklin Roosevelt, and Ronald Reagan.

The plain and simple fact is that the Senate Republicans profoundly abused their power and violated the spirit of our Constitution and of our constitutional traditions for one reason and one reason only – to prevent a duly elected president from appointing to the Supreme Court an eminently qualified and properly confirmable justice in the rank partisan hope that the next president – hopefully a fellow Republican – would then appoint a justice more to their ideological liking.

And, sadly, when all the dust settled, they actually got away with it. No better than burglars, they got away with it. Instead of acting in accord with long-settled constitutional principles and traditions, they violated the norms of the Supreme Court appointments process and deliberately abused their authority for rank partisan advantage.

Their unconscionable behavior will rightly cast severe doubt on the legitimacy of whatever individual President Trump appoints in place of Chief Judge Garland. Every vote that justice casts in the future will be called into question, because that justice will be sitting on the Supreme Court bench because of nothing less than a constitutional coup d’etat. Through no fault of his or her own, that justice will be seen as an interloper who should never have been appointed to the Court.

It is interesting to recall the last time that politicians tried in so blatant a manner to manipulate the makeup of the Supreme Court in violation of long-standing norms. The year was 1937. President Franklin Roosevelt was furious that a majority of the Supreme Court insisted on invalidating progressive legislation that was intended to help ease the miseries of the Depression. In desperation, Roosevelt proposed a “court-packing plan” that would have enabled him to expand the size of the Supreme Court, make additional appointments, and thus control the future course of the Court’s decisions.

Although Democrats across the nation supported the underlying legislation the Court persisted in invalidating, Democratic members of Congress rejected Roosevelt’s plan. Indeed, even Roosevelt’s Vice-President, John Nance Garner, publicly scorned the plan as unprincipled. In short, those Democrats – those principled public servants – understood that even a crisis like the Depression could not justify so craven a distortion of the traditional procedures and practices of government in order to achieve politically desired ends.

As a sign of the moral corruption that now plagues our nation, though, in this instance Senate Republicans, caring more about outcomes than principles, ruthlessly distorted the advice and consent process in order to attain partisan political ends. That this happened is nothing short of disgraceful. Let us not forget their shameful abuse of authority. And let us not forget that President Trump’s first appointment to the Supreme Court will in fact be an illegitimate interloper who has absolutely no business being the decisive vote in critical Supreme Court decisions in the years and decades to come. By this act, Senate Republicans have undermined the credibility and the legitimacy of an essential branch of our national government. Shame on them.