Abortion-rights activists celebrate outside the Supreme Court following its decision in Whole Woman’s Health v. Hellerstedt. PHOTOGRAPH BY EVAN VUCCI / AP

With its ruling today in the Texas abortion case Whole Woman's Health v. Hellerstedt, the Supreme Court reinvigorated the “undue burden” standard, and with it the fundamental right to abortion. “Undue burden” is the test that courts have been using since 1992 to evaluate whether state laws on abortion are constitutional. In Planned Parenthood v. Casey that year, the Court declared, “An undue burden exists and therefore a provision of law is invalid if its purpose or effect is to place substantial obstacles in the path of a woman seeking an abortion before the fetus attains viability.” As a bulwark protecting abortion rights, that language sounded fairly solid: the application of the purpose-or-effect test to abortion jurisprudence was one of the signal contributions of Sandra Day O’Connor, and it had the markings of her pragmatic approach.

In practice, though, the standard has been applied weakly and inconsistently. Even in Casey, the Court struck down only one provision of the Pennsylvania law in question: a requirement that a woman seeking an abortion notify her husband. The court did not deem any of the law’s other restrictive provisions—including counselling on the dangers of abortion, a twenty-four-hour waiting period, and parental permission for minors—unduly burdensome.

As my colleague Jeffrey Toobin noted, in 2014, “The key phrase did not have a fixed, self-evident definition. And as the Court moved to the right, following O’Connor’s resignation, the scope of the constraints on state power began shrinking.” There was always the possibility, though, that the undue-burden concept could be applied more rigorously. In a law-review article called “Giving Casey Its Bite Back,” published in 2013, Emma Freeman, then a law-school student, argued that good “undue burden” analysis would mean evaluating a law for “the weight of the burden, the legitimacy of the state’s regulatory purpose, and the sufficiency of the relationship between them.” In other words, it was legitimate to look at the nexus between the purpose and the effect of an abortion law. Were the state’s ostensible ends (say, protecting women’s health) actually met by the means it settled on (say, requiring abortion clinics to operate as ambulatory surgical centers)?

In this week’s opinion, written by Justice Stephen Breyer, the Court appears to have done the real weighing of costs and benefits which the test deserves. At issue were two provisions of a law passed in 2013 by the Texas state legislature: one requiring all doctors who perform abortions to have admitting privileges at nearby hospitals, and one specifying that all clinics providing abortions must be retrofitted to meet the elaborate standards of ambulatory surgical centers. As a result of the new restrictions, about half of the forty-one facilities providing abortions in Texas have already closed; ten more would have closed if the law had remained in effect. (There was an injunction blocking the surgical-center provision.)

The court looked closely at the facts of abortion availability and safety in Texas. A series of studies led by Daniel Grossman and the Texas Policy Evaluation Project documented a host of what could certainly be called burdens on women seeking abortions in Texas since the passage of the 2013 law. These included longer waiting times and travel distances, as well as projected increases in self-induced abortions and abortions postponed until the second trimester of pregnancy. Because, as Justice Breyer points out, abortion was already an extremely safe procedure in Texas (and the rest of the country) before the law, none of these disadvantages were offset by a boon to women’s health after it.

Of the admitting-privilege requirement, Justice Breyer’s opinion points out “that, when directly asked at oral argument whether Texas knew of a single instance in which the new requirement would have helped even one woman obtain better treatment, Texas admitted that there was no evidence in the record of such a case.”

As for the mandate that abortions be performed in surgical centers, Breyer notes, “Nationwide, childbirth is 14 times more likely than abortion to result in death, but Texas law allows a midwife to oversee childbirth in the patient’s own home. Colonoscopy, a procedure that typically takes place outside a hospital (or surgical center) setting, has a mortality rate 10 times higher than an abortion. The mortality rate for liposuction, another outpatient procedure, is 28 times higher than the mortality rate for abortion.”

In fact, it’s clear that laws like the one in Texas are not the product of some new enthusiasm for promoting women’s health but of a resourceful anti-abortion movement. The lieutenant governor of Texas, David Dewhurst, gave the game away with a tweet the day after the Texas law passed the Senate. Above an image of a poster from a pro-choice group warning that the bill would essentially ban abortion statewide, he wrote, “We fought to pass SB5 through the Senate last night, & this is why.”

With the majority opinion in this week’s case and its reanimation of the “undue burden,” the Court signalled trouble ahead for that approach, not only in Texas but in other states—including Oklahoma, Louisiana, and Wisconsin—where similar laws are currently blocked by lower courts. As Justice Ruth Bader Ginsburg wrote in a concurring opinion, laws that “ ‘do little or nothing for health, but rather strew impediments to abortion,’ cannot survive judicial inspection.”