The Supreme Court. (Win Mcnamee/Getty Images)

Laurence H. Tribe is a professor of constitutional law at Harvard Law School. Joshua Matz practices law in the District and clerked for Supreme Court Justice Anthony M. Kennedy from 2014 to 2015. They are the co-authors of the 2014 book “Uncertain Justice: The Roberts Court and the Constitution.”

With 24 cases still to decide this term and only eight justices to decide them, the Supreme Court has mustered all its resources to find (or manufacture) consensus. Many rulings — even those with lopsided majorities — hint strongly of compromise. So far, the justices have mostly decided not to decide, drafting narrow opinions that leave big questions unanswered.

It is in vogue to treat this term as a one-off, yet another result of madhouse election-year politics. On that view, the court just needs to tread water a while longer. In the meantime, each of us can hope that justices who share our particular vision will end up with a majority.

But when “exceptional” circumstances endure long enough, advance powerful political interests and are tolerated by the public, they can easily become the new normal. One or more vacancies will likely arise soon enough, leaving the court’s ideological balance up for grabs. Especially in times of divided government, the historic norm of swift confirmations might be cast aside — replaced by lengthy delays that partisans on both sides will opportunistically decry or defend.

Long after the current vacancy is filled, eight-justice courts may occur with depressing regularity.

To many exhausted or dismayed by the court’s recent pyrotechnics — which include landmark rulings on gun rights, campaign finance, same-sex marriage, health care and racial equality — the notion of a lower-profile court is appealing. Of course, this spell of judicial restraint may be extinguished when a ninth justice is confirmed. But that has not stopped those who prefer a chastened judiciary from declaring eight-justice courts a boon to democracy or, at very least, a trivial issue.

Their view misses crucial aspects of the court’s role.

To start, power abhors a vacuum. As important questions of federal law arise, an eight-justice court’s power could flow downward, to the regional courts of appeals. Establishing the (more liberal) U.S. Court of Appeals for the 9th Circuit as a de facto “Supreme Court of the West” — or the (more conservative) 5th Circuit as a “Supreme Court of the South” — is a dispersal of judicial power, not a weakening. In some cases, moreover, an absentee court could embolden more aggressive lower court judges to flex their muscles. When the justices are limited by obstructionism rather than by a consensus favoring restraint, thunderbolts may cease on the mountaintop only to intensify on the hills below.

Besides, when lower courts disagree, it is not “judicial modesty” to avoid refereeing. The Constitution should not mean one thing in Texas but another in California. Prolonged legal uncertainty can chill valuable economic and political activity, and inflict grave harm on individuals. The Supreme Court must tame forces of fragmentation and vindicate the principle that we are a single union; a series of eight-justice courts would struggle to fulfill that duty.

Equally harmful are instances when a divided court punts on questions that ultimately require judicial disposition. That is certainly true of constitutional cases, where the court’s word is usually final. But even in matters of economic regulation, environmental protection and anti-discrimination law, political gridlock typically means that the court alone can end disputes.

In such cases, artful evasion may eliminate the only forum able to authoritatively settle charged issues, thus inflaming the very tensions that have stalled confirmations in the first place. Further, continued half-measures can keep the court mired for years in bitter political fights, as shown by the ongoing saga surrounding Obamacare’s contraception mandate. While there is a time for narrow compromise, sometimes prudence favors a broader resolution — which might be impossible for an eight-justice court to achieve.

As a worst-case scenario, it is terrifying to contemplate a divided court unable to offer the nation finality in the face of a major constitutional or electoral crisis.

In any event, defenders of a hyper-restrained court must be careful what they wish for. There is a profound arbitrariness to freezing the law wherever it stood when the most recent vacancy arose. Whatever the Constitution allowed or prohibited at that moment could become a years-long status quo, entrenching even highly controversial rulings.

Put simply, paralysis does not equal restraint. Nor does it achieve any other worthy constitutional goal. When new questions arise — whether about encrypted iPhones or transgender rights — the court implements the Constitution and federal statutes, deciding which issues are left to democracy and what rights it must protect. A parade of eight-justice courts could stunt this growth of federal law in strange and random ways.

It would be especially sad to see the court hobbled in an era of shattered faith in our political institutions. The court remains uniquely effective, but its legitimacy is hard won and easily lost. The justices are understandably sensitive to this fact. Perhaps that is why several have offered assurances that all is well, along with timely defenses of judicial caution.

Sustained bouts of indecision, however, exact a heavy toll. We need branches of government capable of doing more than treading water: They must actually function. The public can tell the difference.