Five days after North Carolina passed the most anti-LGBTQ law in the country, a coalition of groups led by the American Civil Liberties Union filed a lawsuit to block the measure as a violation of the U.S. Constitution. The suit constitutes a straightforward challenge to North Carolina’s assertion that it can exclude trans people from the bathroom that aligns with their gender identity and nullify local LGBT nondiscrimination ordinances. But it is also a bold attempt to assert new constitutional protections for gay and trans individuals in the wake of Obergefell v. Hodges.

The complaint names three individual plaintiffs: a trans employee at the University of North Carolina; a trans University of North Carolina student; and a lesbian at North Carolina Central University School of Law. These are the perfect plaintiffs, because they allow the ACLU to challenge a key illegality in the North Carolina law (dubbed HB2): It explicitly discriminates against trans people by barring them from using the correct bathroom in any government facility, including public universities. Federal law prohibits discrimination against trans students in schools that receive federal funding—as UNC does. So the ACLU lawsuit effectively highlights the direct clash between HB2 and an existing federal mandate, forcing the state to choose between continued discrimination and continued education funding.

But the real power of the lawsuit lies in its constitutional challenge. Although it’s just a complaint—the opening volley in what is sure to be extended litigation—the suit lays out a compelling case for HB2’s unconstitutionality on several fronts. First, the complaint notes that, “by singling out LGBT people for disfavored treatment and explicitly writing discrimination against transgender people into state law, H.B. 2 violates the most basic guarantees of equal treatment and the U.S. Constitution.” That is a recitation of Romer v. Evans, the very on-point 1996 precedent in which the Supreme Court found that the Equal Protection Clause forbade Colorado from overriding local gay nondiscrimination ordinances. This Romer challenge is likely to succeed—especially since, as the complaint notes, the legislative process preceding the passage of HB2 was “rife with procedural irregularities,” and lawmakers “made no attempt to cloak their actions in a veneer of neutrality, instead openly and virulently attacking” LGBTQ people. These facts reveal that HB2 was motivated by animus, an improper legislative purpose.

Romer, however, is only the start of the salvo. The ACLU also asserts that the Equal Protection Clause’s long-recognized bar on sex discrimination encompasses discrimination on the basis of gender identity—including exclusion of trans people from public bathrooms. That theory of the clause, once a novel legal proposition, has lately become conventional wisdom. In 1989, the Supreme Court found that “sex stereotyping”—discrimination against an individual for failing to conform to a certain sex—qualifies as sex discrimination in the context of employment discrimination. Federal courts have since extended this rule to encompass anti-trans discrimination, which inherently involves sex stereotyping, since the discriminator believes the trans person is not properly conforming to their assigned sex. Now the ACLU wants to use the North Carolina litigation to enshrine the rule as a constitutional value.

If the ACLU succeeds, trans people across the country would instantly receive considerable constitutional protections. Under the Equal Protection Clause, sex discrimination is subject to heightened scrutiny, requiring an “exceedingly persuasive justification” to survive constitutional review. If trans discrimination is sex discrimination, then any anti-trans law, too, would have to be supported by an “exceedingly persuasive justification.” In effect, that means the bathroom predator myth—the notion that sexual predators pretend to be trans in order to assault women in bathrooms—will not pass muster, because it is a complete fiction. No bathroom bill will pass constitutional muster.

There are, of course, many hurdles between the ACLU’s Monday complaint and a Supreme Court ruling granting trans people robust constitutional protections. But if this gambit pays off, then North Carolina’s effort to disfavor and dehumanize trans people will boomerang in a pretty stunning way. In passing HB2, the state meant to single out trans people and deprive them of their dignity. The ultimate result of this effort might just be an affirmation of trans equality by the federal judiciary.