As the political battle over the vacancy created by the sudden death of Justice Ruth Bader Ginsburg intensifies, a great deal of attention will be paid to the fate of the landmark Supreme decision Roe v. Wade, and for good reason. But the first potentially historic opinion the court will be considering in the fall will not concern reproductive rights. On November 10 — exactly one week after one of the most important elections in American history, the Supreme Court will hear oral arguments in California v. Texas, the latest legal challenge to the Affordable Care Act. Not only will the health care of tens of millions of people be on the line — so too could the very future of the Supreme Court itself.

The argument made by the Attorneys General of Texas and 17 other states whose governors oppose the Affordable Care Act is that it suddenly became unconstitutional when Congress passed a large upper-class tax cut in 2017. One obscure provision of the new statute eliminated the tax penalty that adults who chose not to carry health insurance had to pay under the Affordable Care Act. The so-called "individual mandate" remained in the law but there would be no penalty for violating it. According to the state plaintiffs, this is a constitutional problem, since Chief Justice Roberts' opinion in NFIB v. Sebelius held that the individual mandate exceeded Congress' power to regulate interstate Congress but was constitutional under the federal tax power. Furthermore, they argue that the mandate cannot be severed from the rest of the law and therefore most or all of the rest of the statute (including the protections for patients with pre-existing conditions and the historic expansion of Medicaid) have to be struck down.

If that argument sounds specious to you, you're right. Particularly weak is the idea that the now unenforced mandate is so essential to the rest of the ACA that the rest of the statute cannot survive without it. Under current Supreme Court doctrine, an unconstitutional provision is severable unless it is established that Congress would have preferred to not enact the law than to enact it without the relevant provision. But we know Congress' preference: If Congress believed that eliminating the tax penalty would make the rest of the statute unworkable, they presumably would have repealed it — but they did not. Indeed, the argument is so weak that even some of the most prominent supporters of previous rounds of anti-ACA litigation have called the suit legally baseless.

But weak as the argument is, both a Republican District Court judge and two-Republican nominated judges on a 3-judge Fifth Circuit panel bought it. While Justice Ginsburg was still on the court, the suit had little chance at the Supreme Court — if Chief Justice Roberts was unwilling to strike down the ACA before most of it had gone into effect in 2012, it's hard to imagine he would vote to take health care away from tens of millions of people based on legal arguments that are even worse now. But the calculus has changed. If a Ginsburg replacement has not been confirmed yet, an eight-justice Supreme Court would hear the case, but because the 5th Circuit ruled against the ACA, its ruling would stand if the Supreme Court deadlocked. If McConnell does get a replacement confirmed before the election — by far the most likely outcome — the ACA's opponents won't need Roberts' vote to get the act struck down, and the lower court decisions indicate that the default position of Republican nominees is to favor the suit.

A ruling that the ACA is unconstitutional next spring would be a political earthquake. Huge numbers of people would lose access to health care. Moreover, if Democrats re-take the White House and the Senate, they will be considering proposals to take measures to counter the Trumpified federal judiciary, such as expanding the number of seats on the Supreme Court. A decision that would strip tens of millions of people of their health insurance based on legal arguments so weak that to re-state them is to refute them would be a gift to people who favor expanding the judiciary (and other reform measures, such as granting statehood to Washington, D.C., and Puerto Rico).

The court may decide it doesn't want to take up this fight right away. Justice Brett Kavanaugh, who has previously argued that there should be a strong presumption of severability, could join with Roberts and the court's three remaining liberal judges to uphold the non-mandate provisions of the ACA. It would also be wise for Congress to try to pre-empt the suit by simply repealing the mandate, one of many excellent reasons for why a Democratic Senate should eliminate the filibuster, as Senate Republicans would not allow the Senate to fix the law otherwise.

But even if the ACA survives the latest bad faith challenge, with a 6-3 Republican majority it cannot be considered safe for the long-term, and the same can be said of any major legislation passed by a future Democratic Congress or regulatory measure taken by a Biden administration. Democrats will have to seriously consider how they will respond if an entrenched, extremely partisan Republican majority on the Supreme Court refuses to allow the people's representatives to govern.

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