Hawaii Attorney General Douglas Chin speaks at a press conference after filing an amended lawsuit against Donald Trump's travel ban on March 9, 2017.Hugh Gentry / Reuters

Democrats were ecstatic when a judge in Honolulu barred enforcement of the Trump administration’s travel ban. They were thrilled when a judge in Chicago halted a policy to rescind grant funding to sanctuary cities. In both cases, the judges extended their ruling beyond the litigants to the whole country, issuing so-called national injunctions.

For opponents of Donald Trump’s administration, this legal maneuver has seemed like a godsend. Now it may come back to haunt them, as a single federal judge in Texas considers putting the Affordable Care Act on ice—not only in Texas, but anywhere in the country.

Can one judge really impose his ruling from one coast to the other?

A group of Republican state attorneys general certainly think so. In their view, Congress knocked the constitutional legs out from under Obamacare when it repealed the penalty for going without insurance. They’ve sued to stop the federal government from implementing any part of the law—including its protections for preexisting conditions and the Medicaid expansion—across all 50 states.

What’s more, they might win. Their legal arguments are thin, but the Republican attorneys general filed their case in Fort Worth, Texas, knowing they’d draw a conservative judge who’d be sympathetic to their cause. In a hearing, that judge suggested he was inclined to side with the attorneys general. Within weeks, he could issue an order enjoining all or part of the law.

Something is very wrong with this picture. Under the Constitution, the federal courts are vested with “judicial Power,” which has traditionally been understood to limit them to resolving disputes between the parties who appear before them. That makes sense in a democracy: Unelected judges shouldn’t adjudicate the rights of nonparties or referee abstract political fights.

In a quiet shift over the past 60 years, however, the courts have gradually assumed the power to enter national injunctions against federal statutes and regulations, at least under some (not very well-defined) circumstances. The trend has accelerated dramatically in the past three and a half years, as claims of executive overreach have proliferated.

The Supreme Court has not expressly ruled on the legality of these national injunctions, though it has recently shown some interest in the issue. In our judgment, the Court should curtail the practice.

The point is not a partisan one. (One of us is a Republican, the other a Democrat.) Before courts entered national injunctions against the Trump administration, they used them to thwart the Obama administration’s rule for overtime pay and its signature immigration policy, Deferred Action for Childhood Arrivals.

National injunctions are equal-opportunity offenders.

On a legal level, they’re dubious. Under the Constitution, a plaintiff must have standing in order to sue, which means she has to show that the relief she seeks will remedy an injury that she’s suffered. She doesn’t have standing, however, to seek relief for someone who has not brought a lawsuit. That’s one reason the Supreme Court has insisted that “injunctive relief should be no more burdensome to the defendant than necessary to provide complete relief to the plaintiffs.” And that’s why, in our assessment, a court oversteps its authority when an injunction does more than benefit the plaintiffs who have sued.

There is, in fact, a perfectly constitutional way to bring a large group of plaintiffs before a court. It’s called a class action, and it’s governed by a complex set of legal rules designed to protect plaintiffs who want to opt out. National injunctions sidestep those rules.

The policy worries run deeper. Although federal law is supposed to be the same across the land, the court system in the United States tolerates and even encourages some variation. When a dispute arises before an Oregon district-court judge, for example, she is obliged to follow the decisions of the Supreme Court and the Court of Appeals for the Ninth Circuit. She’s perfectly free, however, to disregard rulings from any other court.

As it turns out, federal judges often disagree with one another. That’s healthy. No single judge will get it right all the time, so it’s better to give many different judges a chance to wrestle with a tough legal question. If conflict persists, the Supreme Court can always intervene. By the time it does, its decision will be informed by the views of dozens of smart judges across the country.

National injunctions short-circuit that process. Instead of allowing many judges to reach independent judgments, they resolve the question for all courts. The government has little choice but to appeal, sometimes all the way up to the Supreme Court, foreclosing the chance for further percolation of the legal question.

Worse, national injunctions encourage forum shopping. Because a litigant only has to win in a single court to stop the implementation of a congressional statute or agency rule, he has a huge incentive to pick a jurisdiction where he’s likely to win. It’s no coincidence that the latest Obamacare suit was filed in Texas. It’s also no coincidence that many of the high-profile challenges to Trump policies have been brought in deep-blue states.

There’s even a risk of dueling injunctions. In September, for example, the Maryland attorney general asked a Maryland court to enter an injunction requiring the Trump administration to keep enforcing the Affordable Care Act. There’s a decent chance that one judge will enjoin Obamacare, even as another orders the Trump administration to faithfully execute the very same law.

That’s no way to govern a country. Injunctions should provide relief to the parties who sue, not to people who don’t sue. A recently introduced bill—the Injunctive Authority Clarification Act of 2018—would clearly affirm this important principle. We hope Congress passes some version of the bill. If it doesn’t, the Supreme Court should put an end to national injunctions.

That would doubtless upset those who’ve grown used to thwarting government actions through the court system. But the United States is a fractious, complicated democracy, and it’s disconcerting how much authority we’ve ceded to lone, unelected judges.

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