The Department of Health and Human Services today announced a proposed rule undermining protections for transgender people regarding discrimination in health care.

It stands to affect 1.4 million transgender adults and 150,000 transgender teens ages 13 to 17 in the U.S., according to the Williams Institute, a research organization at the University of California, Los Angeles, School of Law.

The rule deals with enforcement of Section 1557 of the Affordable Care Act. A regulation dating from President Barack Obama’s administration asserts that Section 1557’s prohibition on sex discrimination also bans discrimination based on gender identity and discrimination against people who have had abortions. The Obama-era regulation has been blocked by lawsuits from going into effect, though, and in issuing a new proposed rule today, Donald Trump’s administration defines sex discrimination more narrowly.

"When Congress prohibited sex discrimination, it did so according to the plain meaning of the term, and we are making our regulations conform," said a statement released by Roger Severino, director of the HHS Office for Civil Rights, who has a long record of anti-LGBTQ activism.

During a press briefing, he added, "We have concluded in our most recent filing with the court that discrimination on the basis of sex does not cover gender identity," NPR reports.

Section 1557 will remain a federal law, so people who believe they’ve suffered discrimination based on gender identity or previous health care decisions will still be able to sue, and activists encourage them to do so. Some courts have ruled that sex discrimination includes gender identity discrimination. But the federal government will not be on their side.

The rule is subject to a 60-day period of public comment before it becomes final, but if it does, it will have a devastating effect, the Williams Institute’s scholars predict, especially for trans people who live in states with no protections against gender identity discrimination in public accommodations, such as health care. They estimate that more than 780,000 transgender people — 705,000 transgender adults and 78,000 transgender youth — live in these states, so the federal law is the only protection they have.

“Explicit gender identity protections were adopted in response to an overwhelming record of anti-transgender discrimination and barriers to health care and health coverage,” Williams Institute Executive Director Jocelyn Samuels, the former director of OCR who led the process of drafting the original regulations implementing Section 1557, said in a press release. “A reversal of these protections would be contrary to numerous court decisions and any fair reading of the statute and would seriously endanger the health and well-being of an especially vulnerable population.”

The civil rights group Equity Forward said it obtained, through a Freedom of Information Act request, emails that show Severino knew the new proposed rule would harm more people than initially projected. “The Trump administration has weaponized the HHS Office for Civil Rights to systemically deny health care to transgender people. This office previously defended people who were discriminated against, but this administration is hellbent on stripping protections from the people it is sworn to protect. These policies are nothing more than transphobic bigotry," said a statement from Mary Alice Carter, senior advisor for the group.

Other civil rights organizations were likewise quick to condemn the new proposed rule. Mara Keisling, executive director of the National Center for Transgender Equality, also estimated the number of people affected at 2 million, higher than the Williams Institute's numbers.

"Predicated on little more than prejudice, this proposal will abandon 2 million Americans who already face significant barriers to accessing adequate and life-saving health care," she said in a press release. "This is not about free health care or special treatment. It’s about the right of every American to be treated with dignity when they walk into an emergency room, meet a new doctor, or find the right insurance plan. If permitted, this rule will promote ignorance and hate that no American should have to face while seeking care, and we are ready to fight it with everything we’ve got."

“This move by the Trump administration is nothing less than an act of violence against those whose health care needs have historically been ignored, neglected, and dismissed," said a statement issued by Louise Melling, deputy legal director with the American Civil Liberties Union. "Transgender and nonbinary people experience staggering rates of discrimination from health care institutions and providers. They face the denial of medically necessary health care related to gender transition, harassment from medical providers, negligent care, and the refusal of medical service altogether. The administration wants to take away protections to stop that discrimination, an action that will lead to devastating health consequences. The proposed changes would also strip protections from people based on reproductive healthcare decisions, including whether they have had an abortion.” If the rule becomes final, the ACLU will sue, she added.

Studies have indicated that up to 70 percent of trans Americans have experienced discrimination in health care, according to the Human Rights Campaign. And HRC noted that the Obama-era rule also covered discrimination based on sex stereotyping, and that is being gutted by the Trump administration, potentially affecting lesbian, gay, and bisexual people as well. “The administration puts LGBTQ people at greater risk of being denied necessary and appropriate health care solely based on their sexual orientation or gender identity," said David Stacy, HRC government affairs director, in a press release. "Everyone deserves access to medically necessary care and should never be turned away because of who they are or who they love.”

Lambda Legal urged those who have suffered discrimination to fight back.

“No matter how ardently Trump administration officials may want to gut the civil rights protections in our federal laws, only Congress and the courts have that power," said a statement released by litigation director Diana Flynn. "This latest assault on our rights will not go unchallenged. Anyone who experiences mistreatment in health care services based on their sexual orientation, gender identity or HIV status should contact our Legal Help Desk to discuss their potential legal options. In matters of health, such an assault is especially pernicious and potentially life-threatening. Today’s announcement from HHS is not the last word — Lambda Legal will use every tool in our arsenal to defend LGBT people from the kind of discrimination that this proposal intends to unleash.”