The three-judge panel ruling of the D.C. Circuit Court of Appeals on recess appointments in Canning v. NLRB was stunning.

The three Republican-appointed judges rejected a century or more of common presidential practice and gave an unprecedented interpretation of the scope of recess appointments. They said that unless vacancies occurred during the one period they defined — ignoring how Congress defines its own recesses — they could not be filled by recess appointments.

If the decision holds, it would, among other things, call into question every 5-4 decision made by the Supreme Court during the two years that Justice William J. Brennan Jr. served on a recess appointment, not to mention the decisions promulgated by the other federal judges who also have served on the same basis along with all decisions made by the National Labor Relations Board and other regulatory bodies with recess appointees.

This was a remarkable exercise of judicial overreach and arrogance. It was not all that surprising coming from Judge David Sentelle, who almost single-handedly destroyed the concept of even-handed justice under the Independent Counsel Statute when he dropped the supremely competent and fair Robert Fiske and replaced him with Kenneth Starr during the Clinton administration and then followed with several other avenging angel independent counsels to hound other Clinton officials.

Sentelle is also the man behind the SpeechNow.org v. Federal Election Commission decision that followed Citizens United v. FEC and made a mockery of the notion of independence from candidates and campaigns that was the linchpin of Justice Anthony Kennedy’s reasoning for the “independent groups” funded through unlimited contributions from individuals, corporations and shadow organizations, which was so devastatingly skewered by Stephen Colbert.

I am not a fan of excessive use of recess appointments, especially when they are made to avoid a major controversy or the simple inconvenience of a possible negative vote in the Senate. But those kinds of recess appointments were made more frequently in the Reagan, Clinton and George W. Bush years than in the Obama presidency. Our current president has issued few recess appointments and did so only when faced with unprecedented filibusters against qualified and widely admired nominees who were opposed because Republicans wanted to emasculate their agencies in violation of common practice and the fiduciary duty of lawmakers to allow laws to be administered and implemented.

The Canning decision stands alone against several other appeals courts with very different approaches to recess appointments, and the case will almost certainly reach the Supreme Court. But in the meantime, the president has to face a grim reality: His appointments to all positions, executive and judicial, are now held hostage to the whims or strategies of a minority of senators.

Senate Majority Leader Harry Reid, D-Nev., did the right thing in avoiding a unilateral Democratic move to alter the filibuster rule, instead reaching a compromise with Minority Leader Mitch McConnell, R-Ky., that will make it easier to overcome individual holds on judges and many executive nominees and to move nominations en bloc when the two leaders combine to thwart one or a handful of renegades.

But if McConnell decides to violate the spirit of that agreement and stage partisan filibusters of nominees — and can keep 40 of his troops together — he can stop a president’s appointees in their tracks and in the process can kill agencies and stymie programs.

We can expect this to happen with the NLRB, where Republicans will keep the agency below its required quorum and thus prevent it from acting, and with the FEC, where McConnell will keep all five of the current commissioners whose terms have expired in office to keep the agency deadlocked and impotent.

We can expect it to happen with the previously successful attempts to devastate the Centers for Medicare and Medicaid Services, so it cannot effectively implement the health care law, and with the Consumer Financial Protection Bureau, so Senate Republicans can put a huge roadblock in the implementation of Dodd-Frank financial regulation and allow banks to operate without restraint.

It is likely to happen with appointees to the Independent Payment Advisory Board, the best hope for controlling Medicare costs. And it would not be surprising if Senate Republicans try to stall a slew of Obama nominees for appeals courts, especially the D.C. Circuit.

If these things happen, I would be surprised if Reid does not revisit the filibuster issue midsession, using the same technique his predecessor, Bill Frist, raised a few years ago as a possibility to overcome judicial holds and filibusters. That would be unfortunate on many fronts. But there is an easy way to avoid it — for McConnell to show that the deal he reached with Reid was indeed in good faith and that the Senate will return to its long-standing norms where party-driven filibusters were rare and reserved for issues of great national moment and a handful of nominees who had real issues of competence or moral turpitude.

Norman Ornstein is a resident scholar at the American Enterprise Institute.