The Supreme Courts upcoming decision about the most common pharmaceutical used for medication abortions may be just the beginning of the political battle over the drug.

Earlier this month, the Supreme Court agreed to hear an appeal of lower-court rulings that would severely reduce access to mifepristone. The Courts acceptance of the case marked a crucial juncture in the legal maneuvering over the medication.

But however the high court rules, pressure is mounting inside the GOP coalition for the next Republican president to broadly use executive authority at the Food and Drug Administration and the Justice Department to limit access to mifepristone and to reduce what abortion opponents call chemical abortion.

Chemical abortion will be front and center and presented front and center by the pro-life movement if there is a Republican president, Kristan Hawkins, the president of Students for Life of America, told me. There is going to be a lot of action we want to see taken.

The possibility of new executive-branch restrictions on abortion drugs, which are now used in a majority of all U.S. abortions, underscores the stakes over abortion in the 2024 presidential election. Even if Donald Trump or another Republican wins back the White House next year, they might not have enough votes in Congress to pass a nationwide ban on the practice. But through executive action, the next GOP president could unilaterally retrench access to mifepristone in every state, however the Supreme Court decides the current case. Multiple former FDA officials and advocates on both sides of the issue told me that through regulatory and legal actions by the FDA, the Justice Department, or both, the next Republican president could impose all the limits on access to mifepristone that anti-abortion groups are seeking in the lawsuit now before the high court.

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The FDA is a highly regulated space, so there are a lot of hoops they would have to jump through, Jeremy Sharp, the FDAs deputy commissioner for policy planning, legislation, and analysis during part of Barack Obamas second term, told me. But if they got a commissioner in there that was ideologically motivated, and if they changed the staff leadership, then theres a lot they could do before anybody could get in the way and stop them.

The growing Republican focus on using executive-branch authority against abortion access marks a new front in the broader political confrontation over reproductive rights. While Roe v. Wade was in place, the social conservative movement was focused overwhelmingly on trying to reverse the nationwide right to abortion and wasnt zoned in on this issue of federal regulatory authority over abortion drugs, Hawkins noted.

Medication abortion involves two drugs: mifepristone followed by misoprostol (which is also used to prevent stomach ulcers). From 2000 through 2022, almost 6 million women in the U.S. used mifepristone to end a pregnancy, according to the FDA. In all those cases of women using the drug, the agency has recorded only 32 deaths (including for reasons unrelated to the drug) and a little more than 1,000 hospitalizations. The risk of major complications has been less than half of 1 percent.

Neither of the past two Republican presidents acted against the drugs administratively or even faced sustained pressure from social conservatives to do so. The FDA initially approved mifepristone for use in abortion during the final months of Bill Clintons presidency, in 2000. But during Republican President George W. Bushs two terms, the FDA made no effort to rescind that approval.

During Obamas final year, the FDA significantly loosened the restrictions on usage of the drug. (Among other things, the agency reduced the number of physician visits required to obtain the drugs from three to one; increased from seven to 10 the number of weeks into a pregnancy the drugs could be used; and permitted other medical professionals besides physicians to prescribe the drugs if they received certification.) During Trumps four years, the FDA did not move to undo any of those decisions.

But the rights focus on abortion drugs has significantly increased since Trump left office. According to Hawkins, one reason is that the COVID pandemic crystallized awareness of how many abortions are performed remotely with the drugs, rather than in medical settings. Even more important may have been the decision by the six GOP-appointed Supreme Court justices in 2022 to overturn Roe. By fulfilling the top goal of anti-abortion activists, that decision both freed them to concentrate on other issues and raised their ambitions.

In one measure of that growing zeal, social conservative groups and Republican elected officials have pushed back much harder against Joe Bidens attempts to expand access to mifepristone than they did against Obamas moves. Under Biden, the FDA has eliminated the requirement for an in-person visit to obtain mifepristone; instead it allows patients to get a prescription for the drug through a telehealth visit and then receive it through the mail. The FDA under Biden has also allowed pharmacies that receive certification to dispense the drug.

As I wrote earlier this year, the paradox is that Bidens rules will be felt almost entirely in the states where abortion remains legal. Almost all red states have passed laws that still require medical professionals to be present when the drugs are administered, and, even though the FDA allows their use through 10 weeks of pregnancy, the drugs cannot be prescribed in violation of state time limits (or absolute bans) on abortion.

Shortly after last Novembers midterm election, an alliance of conservative groups sued in federal court to overturn not only Bidens measures to ease access to the drug but also the changes approved in 2016 under Obama, and even the decision under Clinton in 2000 to approve the drug at all.

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In April 2023, Judge Matthew J. Kacsmaryk, a Trump appointee and abortion opponent, ruled almost entirely for the plaintiffs, striking down the Biden and Obama regulations and the FDAs original approval of the drug. In August, a panel of three Republican-appointed judges on the Fifth Circuit Court of Appeals upheld Kacsmaryks ruling overturning the Obama and Biden regulatory changes. But the panel, by 21, ruled that it was too late to challenge the drugs original approval.

The Supreme Court along the way blocked the implementation of any of these rulings until it reached a final decision in the case, so mifepristone has remained available. In its announcement earlier this month, the Court agreed to hear appeals to the Fifth Circuit decision erasing the Obama and Biden administrations regulatory changes but declined to reconsider the circuit courts upholding of mifepristones original approval. Those choices have raised hopes among abortion-rights activists that the Court appears inclined to reverse the lower courts ruling and preserve the existing FDA rules. We are very hopeful this is an indicator the Court is not inclined to rule broadly on medication abortion and they are concerned about the reasoning of the decisions [so far], said Rabia Muqaddam, a senior staff attorney at the Center for Reproductive Rights, a group that supports legal abortion.

But the legal process has shown that even a Supreme Court decision maintaining the current rules is unlikely to end the fight over mifepristone. The reason is that the proceedings have demonstrated much broader support in the GOP than previously for executive-branch action against the drug.

For instance, 124 Republicans in the House of Representatives and 23 GOP senators have submitted a brief to the Supreme Court urging it to affirm the Fifth Circuits ruling overturning the Obama and Biden actions on mifepristone. By approving and then deregulating chemical abortion drugs, the FDA failed to follow Congress statutorily prescribed drug approval process and subverted Congress critical public policy inerests in upholding patient welfare, the Republican legislators wrote. Republican attorneys general from 21 states submitted a brief with similar arguments in support of the decision reversing the Obama and Biden administrations regulatory actions.

In another measure, a large majority of House Republicans voted last summer to reverse the FDAs decisions under Biden that expanded access to the drugs. Though the legislation failed when about two dozen moderates voted against it, the predominant support in the GOP conference reflected the kind of political pressure the next Republican president could face to pursue the same goals through FDA regulatory action.

Simultaneously, conservatives have signaled another line of attack they want the next GOP president to pursue against medication abortions. In late 2022, the Justice Departments Office of Legal Counsel issued an opinion that the Postal Service could deliver the drugs without violating the 19th-century Comstock Act, which bars use of the mail to corrupt the public morals. That interpretation, the opinion argued, was in line with multiple decisions by federal courts spanning decades that the law barred the mailing of only materials used in illegal abortions.

Conservatives are arguing that the next Republican administration should reverse that OLC ruling and declare that the Comstock Act bars the mailing of medications used in any abortions.

The fact that both Kacsmaryk and Circuit Court Judge James Ho, also appointed by Trump, endorsed that view in their rulings on mifepristone this year offers one measure of the receptivity to this idea in conservative legal circles. As telling was a letter sent last spring by nine GOP senators to major drug-store chains warning that they could be held in violation of the Comstock Act not only if they ship abortion drugs to consumers but even if they use the mail or other freight carriers to deliver the drugs to their own stores.

Trump and his leading rivals for the 2024 GOP nomination, Florida Governor Ron DeSantis and former South Carolina Governor Nikki Haley, have avoided explicit commitments to act against medication abortions. But all of these efforts are indications of the pressure they would face to do so if elected. Hawkins said that anti-abortion groups have chosen not to press the candidates for specific plans on regulatory steps against mifepristone but instead intend to closely monitor the views of potential appointments by the next GOP president, the same tactic signaled by the senators in their letter to drug-store chains. It will make for probably the most contentious fight ever over who is nominated and confirmed for the key positions at the FDA and other relevant agencies, Hawkins told me.

Stephen Ostroff, who served as acting FDA commissioner under both Obama and Trump, told me that future Republican appointees would likely find more success in reconsidering the regulations governing access to mifepristone than in reopening the approval of the drug altogether this long after the original approval. Even reconsidering the access rules, he predicts, would likely ignite intense conflict between political appointees and career scientific staff.

I think it would be challenging for a commissioner to come in and push the scientific reviewers and other scientific staff to do things they dont think are appropriate to do, Ostroff told me. Youd have to do a lot of housecleaning in order to be able to accomplish that. But, he added, Im not saying it is impossible.

In fact, political appointees under presidents of both parties have at times overruled FDA decisions. Kathleen Sebelius, the Health and Human Services secretary for Obama, blocked an FDA ruling allowing the over-the-counter sale of emergency contraception to girls younger than 17; the Biden White House has delayed an FDA decision to ban the sale of menthol cigarettes, amid concerns about a possible backlash among Black voters.

Many legal and regulatory experts closely following the issue believe that a Republican presidents first target would be the FDAs decision to allow mifepristone to be prescribed remotely and shipped by mail or dispensed in pharmacies. To build support for action against mifepristone, a new FDA commissioner also might compel drug companies to launch new studies about the drugs safety or require the agencys staff to reexamine the evidence despite the minimal number of adverse consequences over the years, Sharp told me.

Faced with continuing signs of voter backlash on efforts to restrict abortion, any Republican president might think twice before moving aggressively against mifepristone. And any future attempt to limit the drugthrough either FDA regulations or a revised Justice Department opinion about the Comstock Actwould face an uncertain outcome at the Supreme Court, however the Court decides the current case. The one certainty for the next GOP president is that the pressure from social conservatives for new regulatory and legal action against mifepristone will be vastly greater than it was the most recent two times Republicans controlled the executive branch. We want all the tools in the tool kit being used to protect mothers and children from these drugs, Hawkins told me. Amid such demands, the gulf between the FDAs future decisions about the drug under a Republican or Democratic president may become much wider than it has been since mifepristone first became available, more than two decades ago.