The Navy will allow transgender sailors to dress in accordance with their gender identity while off duty. The dress code clarification comes as the military prepares to roll out a controversial new policy on Friday restricting the service of openly transgender people.

The Navy will permit all transgender service members to “live socially” as “their preferred gender” when they are not in uniform, a U.S. Navy spokesperson confirmed to NBC News. The dress code guidance was sent in an administrative message to troops earlier this week.

"There is no policy that prohibits the ability of a Service Member to express themselves off-duty in their preferred gender," the message states. "Appropriate civilian attire, as outlined in the uniform regulations, will not be determined based on gender."

The new trans military policy set to be unveiled Friday — which was ignited by a series of surprise tweets sent by President Donald Trump in July 2017 — allows currently serving transgender troops and service members who have already received a diagnosis of gender dysphoria to continue to serve in their preferred gender. But after April 12, when the policy goes into effect, no one with gender dysphoria who is taking hormones or has transitioned will be allowed to enlist.

Further, any currently serving troops diagnosed with gender dysphoria after April 12 will have to serve in their sex as assigned at birth and will be barred from taking hormones or getting gender-affirming surgery.

Those guidelines, which the Defense Department insists do not constitute a ban, were announced after the U.S. Supreme Court and the U.S. Court of Appeals for the District of Columbia allowed the Trump administration to enforce the policy while it is being challenged in court. LGBTQ advocacy organizations, including the National Center for Lesbian Rights and GLBTQ Legal Advocates and Defenders (GLAD), have filed lawsuits to overturn the “trans military ban,” calling it “discriminatory.”

As those cases make their way through the court system, LGBTQ groups working on behalf of transgender members of the military credited the Navy for taking a “step forward” to affirm the lived identities of trans sailors.

Bree Fram, communications director at the LGBTQ military advocacy group SPART*A, said the organization is “thrilled.”

“The Navy is taking care of its transgender service members by giving them the option to dress and express themselves as they choose,” Fram told NBC News.

Melody Stachour, a trans woman who serves as a chief petty officer in the Navy Reserve, said the newly announced guidelines are “an attempt to support trans service members to the maximum extent possible, even while they are constrained by the overall policy that they are governed by.”

“This is not just good for the sailors, but also for the Navy,” she said, “as it allows them to retain sailors who are doing an excellent job … while acknowledging that they are still required to follow the orders given by their seniors.”

Others expressed reservation about the Navy guidelines on gender expression, saying it could put transgender people at risk of being discharged from the military.

Although the Department of Defense has maintained the restrictions on trans troops are not a “ban,” a report released by the Palm Center, a nonpartisan public policy think tank, claims the new regulations make it almost impossible for transgender people to serve. According to the report, both “gender dysphoria” and a “medically advised need for any treatment for gender dysphoria” constitute a “basis for separation from military service.”

Aaron Belkin, the Palm Center’s director, claims trans individuals could be reported and sent to a mental health counselor for a “gender dysphoria” diagnosis if they’re seen dressed according to their gender identity off base.

“Once the information gets out that someone is trans, then the service member has no more control over it,” he tells NBC News.

Belkin compares it to life under “don’t ask, don’t tell.” Enacted in 1994, the Clinton-era policy allowed gay, lesbian and bisexual people to enlist in the military as long as they didn’t disclose their sexual orientation. However, closeted troops faced being outed by fellow service members, former partners and even family members.

“In practice, the permission to live a private life was complete B.S.” Belkin added. “It existed on paper, and it's the same mechanism here.”

Andy Blevins, who was discharged under “don’t ask, don’t tell,” said the predicament that faces transgender people serving in the Navy or other branches of the military is actually “worse” than “don’t ask, don’t tell” — which was lifted in 2011.

“We entered the service knowing we had to hide a crucial aspect of our identity,” said Blevins, who now serves as the executive director of OutServe-SLDN, an LGBTQ military advocacy group. “These service members were told nearly three years ago: ‘We see you, we hear you, we’re going to support you, we affirm your identity. Be true to yourself, because that’s what’s needed.’ And then the rug was pulled out from underneath them.”

While Blevins is “grateful” to the Navy for making a gesture to support trans troops, he said the “lack of clarity” surrounding its dress code policies is the issue. As of now, no one knows if it could be used to target transgender service members down the line.

The guidelines issued earlier this week by the military branch advised all members of the military to “continue to treat each other with dignity and respect,” saying there would be “zero tolerance for harassment, hazing or bullying of any service member in any form.”

As the restrictions on trans service go into effect, National Center for Lesbian Rights Legal Director Shannon Minter says these unanswered questions only “underscore the serious harms” of singling out members of an already vulnerable population.

“Gender is a fundamental aspect of a person’s identity,” Minter explained. “It cannot be turned on and off like a switch, and the very notion of requiring a non-transgender person to do so would be immediately recognized as cruel and unworkable. It is equally cruel and unworkable for transgender people.”

According to the Palm Center and OutServe-SLDN, no other branches of the military have announced similar policies regarding the attire of off-duty trans troops.

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