To an extent rarely discussed by the media, Donald Trump’s presidency has been defined by an overwhelming, unrelenting hostility toward the rights of transgender Americans. In just 15 months, the Trump administration has withdrawn federal guidance protecting transgender schoolchildren, employees, and homeless people. It has attempted to outlaw transgender military service and painted trans individuals as disordered deviants who are too mentally unstable to serve. One-third of Trump’s judicial nominees have anti-LGBTQ records, including one who described transgender children as part of “Satan’s plan.”

In the coming weeks, the administration will launch its next attack on trans rights by announcing the revocation of a landmark regulation that protects transgender people from discrimination in health care. The Department of Health and Human Services will argue that the Affordable Care Act does not prohibit doctors and hospitals from turning away transgender patients, or insurance companies from refusing to cover gender-related treatment. This time around, however, civil rights advocates are prepared to fight back. In fact, they’ve already laid the groundwork for a two-pronged legal attack to maintain the ban on anti-trans health care discrimination.

The ACA’s protections for LGBTQ people lie in Section 1557 of the law, which forbids medical providers and insurance companies from discriminating on the basis of race, color, national origin, sex, age, or disability. Like many federal courts, the Obama administration interpreted sex discrimination to encompass discrimination against transgender people on account of their transition from one gender to another. If a medical provider refuses to provide hormone therapy to a transgender man, for instance, it has declined treatment based on his sex, concluding that an individual assigned female at birth should not receive the recommended care. Thus, in May 2016, HHS issued a regulation interpreting Section 1557 to bar discrimination in health care on the basis of transgender status.

In the last weeks of Obama’s tenure, U.S. District Judge Reed O’Connor issued a nationwide injunction blocking the new rule from taking effect. Texas, which sued to block the rule, was able to maneuver the case in front of O’Connor, who had a track record of sweeping decisions that proscribed the Obama administration from implementing LGBTQ-friendly policies. The judge did not disappoint, finding that the rule violated the “religious freedom” of doctors and insurance companies. He also held that the rule unlawfully extended Section 1557’s protections to transgender people, when in fact “sex discrimination” only encompasses “biological differences between males and females.”

Donald Trump’s presidency has been defined by an overwhelming, unrelenting hostility toward the rights of transgender Americans.

This decision flew in the face of Supreme Court precedent defining the contours of gender bias. But instead of appealing it, Trump’s Department of Justice paused the litigation. “New leadership at HHS,” the DOJ told O’Connor in a filing, “has now had time to scrutinize” the trans-inclusive rule and had “concerns as to the need for, reasonableness, and burden imposed by” the policy. Thus, HHS had decided to take “the opportunity to initiate rulemaking proceedings to reconsider the Rule.” Translation: The Trump administration decided to revoke the Obama-era rule and, presumably, replace it with a policy permitting anti-trans discrimination in health care.

Now the administration is reportedly poised to do just that. In April, the DOJ informed O’Connor that HHS had finalized the new rule and will publish it once the White House approves.

LGBTQ advocates have anticipated this move, preparing two lines of attack against the administration’s imminent rollback of Section 1557. The first took the form of a lawsuit filed against the state of Wisconsin on Monday by the National Health Law Program, the civil rights firm Relman, Dane & Colfax, and the law firm McNally Peterson. The suit, filed on behalf of two transgender Wisconsinites, takes aim at the state’s Medicaid program restrictions, which explicitly exclude coverage of any transition-related treatment. It argues that this exclusion violates Section 1557 as well as the Equal Protection Clause of the 14th Amendment.

The Wisconsin lawsuit illustrates an important aspect of Section 1557: It creates a private right to enforce it. That means that while HHS is responsible for enforcing its nondiscrimination protection, individuals can also sue under the law to vindicate their rights independently.

Joseph Wardenski, a lead attorney on the case, told me that while he’s disappointed that HHS “is flouting the law and taking a step backwards,” the ACA’s protections remain enforceable. “Section 1557’s statutory prohibition on sex discrimination forbids discrimination against transgender people seeking medically necessary care,” Wardenski said. While the Trump administration may deny that fact, it can’t stop federal courts from enforcing the law.

But it’s also not at all clear that HHS can actually get away with gutting Section 1557. The lower courts have developed a sizable body of case law establishing that sex discrimination encompasses anti-trans discrimination. And the Supreme Court itself has ruled that “sex stereotyping”—punishing an individual for not complying with gender norms—constitutes discrimination on the basis of sex. When a medical provider declines to treat a transgender patient because it feels he should comport with the sex assigned to him at birth, it’s denying treatment on the basis of a stereotype. The ACA was designed to strike at the entire spectrum of medical discrimination; it would be rather odd to exclude this clear-cut form of gender-based discrimination from the law’s ambit.

For that reason, the American Civil Liberties Union is ready to file suit against HHS as soon as it issues a final rule carving out trans protections from Section 1557. Joshua Block, a senior staff attorney at the ACLU’s LGBT & HIV Project, told me that “from everything we have heard, the proposed rule is based on fundamental errors of law and would jeopardize the health of transgender people.” Moreover, the revision marks an unlawful attempt to rewrite the law in a blatant effort to omit a disfavored minority. Congress directed HHS to bar sex discrimination in health care on the basis of sex; the agency cannot decide to ignore this mandate because it happens to smile upon certain forms of sex discrimination.

This debate is not theoretical. A 2015 survey of transgender people found that 33 percent of respondents had experienced health care discrimination, while another 33 percent did not go to a health care provider because they couldn’t afford it. These findings are in line with other studies that indicate rampant anti-transgender discrimination among both doctors and insurers. The ACA was designed to remedy these problems—yet perversely, the Trump administration is attempting to undermine its solutions. Now it’s up to the courts to declare that Section 1557 means what it says.