THERE IS plenty of time, in the upcoming lame-duck session of Congress, to give President Obama’s nominee for the Supreme Court, Judge Merrick Garland, a hearing and put his nomination to a vote. That vote should be favorable: Mr. Garland, 63, is able, moderate, respected and seasoned, an appellate jurist who has previously been confirmed, with significant Republican support, for the U.S. Court of Appeals for the District of Columbia Circuit.

Of course, this will not happen, because it does not suit Senate Majority Leader Mitch McConnell (Ky.) and his fellow Republicans. Mr. Garland’s nomination should have been considered and voted on in March when Mr. Obama sent his name to the Senate as a replacement for Justice Antonin Scalia. That did not happen because, with the long-term ideological tilt of the court at stake, Mr. McConnell argued that the voters’ choice for president in November should get the pick.

This was a gamble on a GOP victory in the fall; and there is no denying that, in political terms, it has paid off. Contrary to predictions that voters would punish GOP obstructionism, they appear to have rewarded it. President-elect Donald Trump will choose Scalia’s successor next year, a GOP Senate undoubtedly will confirm him — and the court will, in all likelihood, shift rightward rather than left in the coming years. Someday Mr. McConnell’s example may be invoked against his side — those who practice situational ethics must be prepared to have situational ethics practiced against them — but there’s no arguing with his success.

Except to say, perhaps quaintly, that we don’t regard political success as the only relevant measurement here. In addition to the personal injustice to Mr. Garland, the majority leader’s ploy wrought harm to basic norms of democratic accountability. Those should have dictated respect for the majority will, as expressed in the incumbency of Mr. Obama — not anticipatory deference to whatever might happen in November. Any other rule is inherently unstable, as became evident in the waning days of Campaign 2016; when it appeared that Hillary Clinton, not Mr. Trump, might be the winner, Republican politicians started moving the goal posts, suggesting that they might not approve any replacement for Scalia, or even fill subsequent vacancies, until the GOP had regained control of the White House.

In support of his position, Mr. McConnell accurately cited similar musings by then-Sen. Joseph Biden (D-Del.) during 1992, which was then-President George H.W. Bush’s final year in office. To that, we can only reply that this purported “Biden Rule” never should have been treated as a precedent, and would not have been if Republicans had maintained this year the objections to it that they voiced in 1992. Two wrongs don’t make a right, not even in politics.