The legal doctrine of “standing”—a constitutional requirement that that every litigant must meet if they want a court to hear their case—is a quirk of America’s justice system. At its most basic, standing requires you to suffer an injury: a slap in the face, discrimination, adverse government action. If the harm you allege is too generalized or speculative—if you’re upset, for example, that Congress passed a law that you don’t like—the court will dismiss your case. And that result, at least in principle, makes sense. You don’t want courts wasting resources on every frivolous lawsuit in the book.

Two reports from The Wall Street Journal have called into question the standing of the four plaintiffs behind the legal challenge to Affordable Care Act subsidies in 34 states, King v. Burwell, due for oral arguments at the Supreme Court on March 4. That hearing is around the corner, but one law professor, Gerard N. Magliocca of the Indiana University McKinney School of Law, has written that it would be “improper” and “embarrassing” for the court to rule on such an important case without first resolving whether the plaintiffs can claim injury by the healthcare law to begin with. A way the court could address this, Magliocca writes, is by requesting that the parties submit written arguments addressing whether standing is present.

The inquiry should be that simple. If the Supreme Court finds none of the four plaintiffs has suffered as a result of Obamacare, King should be dismissed. But King isn’t just any case. Next to the constitutionality of gay marriage, it’s the biggest case the court will decide this year. And the stakes are huge—not just for President Barack Obama and his signature law, but for millions who stand to lose health insurance if the court agrees that the four plaintiffs have a winning case.

But the Supreme Court, as much as it stands for uniformity and principle, has not been consistent at all in its application of standing, and could very well choose to do whatever it wants with it in King. For one, scholars have found the doctrine of standing far too malleable—susceptible to ideological shifts inside the court and the justices’ own judgments about the role of the court in adjudicating cases and controversies. If the Warren Court in the '50s and '60s was known for increased access to the courts for individuals asserting their rights, the court’s rightward shift under Chief Justices Burger and Rehnquist made access harder—if not explicitly to not give the appearance of awfulness, cunningly by subtly modifying the rules of the game. Namely, by tightening procedural devices, such as standing, all in the name of judicial restraint and separation of powers.

Today, standing is all over the place—it’s even backfired on conservative causes—and the justices have found end-runs around it to decide or not decide cases, often with little explanation. One recent head-scratching example of the court’s confusing stance on standing, 2013's Fisher v. University of Texas, almost dealt a blow to affirmative action policies in colleges and universities. The plaintiff in that case, Abigail Fisher—a white student denied admission at the University of Texas—lacked standing because her only injury before the Supreme Court was the $100 application fee she gave the school; she could not claim an injury for future white applicants because she was alone before the court, and she had enrolled in and graduated from another university anyway. No harm, no foul. The court raised doubts about Fisher’s standing at oral arguments, but it went ahead and decided the case anyway, without ever mentioning standing in its reasoning.  

Other really weird things have happened with standing at the court, and the justices have either remained silent or overexplained themselves. And lest we conclude that standing is a doctrine free of ideology, consider that its specter loomed large in a number of controversial disputes—in Bush v. Gore, in big environmental-law and police brutality cases, and when the court punted on same-sex marriage. There’s no guarantee that the Supreme Court, in itching to reach the merits of King, won’t turn a blind eye to its own rules on who's allowed to get their foot in the courthouse door.