In an unexpected move, the Justice Department filed a brief Thursday night urging a Texas court to invalidate the Affordable Care Act’s crucial insurance reforms — including the prohibition on refusing to cover people with preexisting conditions. Although the ACA is not in immediate peril, the brief represents a blow to the integrity and independence of the Justice Department. It also displays the Trump administration’s contempt for the rule of law.

Last March, a group of red states brought yet another lawsuit seeking to undo the ACA. In their case, they point out (rightly) that Congress, in the tax reform bill, repealed the penalty for going without insurance. They point out (rightly again) that the Supreme Court only upheld the individual mandate because it had been passed pursuant to Congress’s taxing power.

As the states see it, the freestanding requirement to get insurance, which is still on the books, is therefore unconstitutional. The states are probably wrong about that, but never mind. It’s their next move that’s the really audacious one. They argue that because the penalty-free mandate is unconstitutional, the courts must invalidate the entire ACA — lock, stock, and barrel.

Why? Because in the states’ view, Congress believed that the individual mandate was essential to the proper functioning of the rest of the ACA. If it goes, Congress must have wanted the rest of the statute ditched too.

If that sounds inane, that’s because it is. When Congress adopted the individual mandate in 2010, it was an essential part of a broader scheme. But Congress is always free to amend its statutes, even to omit what it previously thought was essential. That’s what Congress did when it wiped out the penalty for going without insurance coverage.

That may have been imprudent: The goal of the individual mandate is to get healthy people to buy insurance, which spreads risk across a broader population and helps keep prices lower for all of us. Without the mandate, insurance premiums are projected to spike.

But Congress is free to make imprudent choices. And here, we don’t have to speculate what Congress would’ve done if it had to choose between invalidating the ACA and eliminating the mandate. Congress made the decision itself: The mandate can go and the rest can stand. For a court to now reject that choice would be the worst kind of judicial activism.

So this should’ve been an easy layup for the Justice Department. In clean, crisp terms, it could simply have explained that when Congress repealed the mandate penalty, it didn’t mean to unravel the entire ACA.

What’s more, the Justice Department had a duty to make that argument. There’s a longstanding, bipartisan commitment to defending acts of Congress whenever a non-frivolous argument can be made in their defense.

This brief, however, torches that commitment. It is hard to explain how big of a deal this is.

This brief could open the door to the Justice Department using flimsy legal excuses not to defend the law

The laws that Congress passes and that presidents sign are the laws of the land. They aren’t negotiable; they’re not up for further debate. If the Justice Department can just throw in the towel whenever a law is challenged in court, it can effectively pick and choose which laws should remain on the books. That’s a flagrant violation of the president’s constitutional duty to take care that the laws are faithfully executed.

But don’t take my word for it. For Justice Department lawyers — and I was one myself (from 2007 to 2010) — the duty to defend congressional statutes is at the core of what it means to be a government attorney. Yet hours before the federal government filed its brief, three line attorneys from the Justice Department withdrew from the case. That’s almost unheard of. These are lawyers who have made arguments they personally disagreed with countless times. They’re civil servants; they’re good soldiers. Yet they could not sign on to the administration’s argument. That’s how outlandish it is.

Do you want to live in a country where the Justice Department can use the flimsiest of arguments to justify declining to defend the law — or even to enforce it? The president has a duty to take care that all the laws are faithfully executed, not just the ones he likes. And while there are cases in which the Justice Department has deviated from that principle, they are extremely rare.

Is there any precedent for this? Odds are we’re going to hear a lot in the coming days about the Obama administration’s decision not to defend the Defense of Marriage Act. And it’s a reasonable case to point to: There, too, the Justice Department refused to defend a statute it deplored.

With the Defense of Marriage Act, however, the Justice Department faced a question about the meaning of the Constitution with deep resonance for the values that we share as a nation. Just as we no longer believe it’s constitutional to offer federal mortgage insurance only in white neighborhoods, the Justice Department concluded that we, as a country, had come around to the view that it was no longer constitutionally tenable to deny equal rights to LGBTQ people.

Whether you agree or disagree with the Justice Department’s decision — and it made lots of people nervous, including me — it was rooted in the public’s evolving sense about what the Constitution meant. By 2011, a justification that once seemed unobjectionable had come to seem untenable.

This case could not be more different from the Defense of Marriage Act. The question is not whether a penalty-free mandate is unconstitutional — who cares, honestly? The critical question, instead, is a technical one about “severability.” No one thinks that fights over severability represent a clash of fundamental constitutional values. No one thinks that severability strikes at the heart of who we are as a people and a country. What’s more, the states’ argument is weak to the point of frivolousness. If that kind of cockamamie argument is a sufficient basis to decline to defend a statute, what isn’t?

I, for one, am concerned. Not so much about the ACA: I still regard it as extremely unlikely that the Supreme Court will adopt an argument as far-fetched as the one the states have advanced. And, so far as I can make out, the Trump administration will continue to enforce the ACA while the litigation progresses. At least for now, no one needs to worry that their insurance will evaporate.

No, I’m frightened for what this says about the rule of law. I don’t like being alarmist about the rule of law — there’s always a risk that in the heat of the moment, it sounds unhinged and naive. But the Trump administration has just announced that it doesn’t care about a law that was passed by Congress and signed by the president. All that matters is that it hates the law and has a (laughable) argument for casting it aside.

That’s not a rule of law I recognize. That’s a rule by whim. And it should scare you too.

Nicholas Bagley is a professor at the University of Michigan Law School and a contributor to the Incidental Economist. Find him on Twitter @nicholas_bagley.

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