AUSTIN — The number of Texas inmates who have identified themselves to prison authorities as transgender is at an all-time high, an upward trend unsurprising to advocates in the face of federal criminal justice reforms and a greater awareness of the transgender community.

According to the Texas Department of Criminal Justice, just 67 inmates in Texas state prisons and jails identified themselves as transgender in September 2014. Two years later, that number has increased almost fivefold, to 333 people.

While still a very small group — just 0.2 percent of the total state jail and prison population — transgender inmates require special attention under new federal rules that seek to reduce inmate sexual assault. Incarcerated transgender people are far more likely to be the targets of violence and rape than the average inmate in the general prison population.

The rules, part of the Prison Rape Elimination Act, require jail and prison officials to provide special accommodations to transgender inmates, including prohibiting strip or cavity searches by a guard of the opposite gender, allowing transgender inmates who have been the targets of violence to be house in protective custody and requiring that officials at least consider an inmate's gender identity when deciding on housing assignments.

Transgender rights advocates were not surprised by the fact that more inmates are openly disclosing their gender identity to prison officials but said the cause of the spike at this point is unknown. One factor, they said, could be a greater familiarity and acceptance of transgender people.

"Both in the free world and among people who are incarcerated, more people who are transgender are coming out, period," said Terry Schuster, a lawyer and expert on the prison-rape law who has written extensively about LGBT inmates. "Transgender rights and transgender identity is just becoming more and more accepted."

"More people who are transgender are coming out, period." - Terry Schuster

In March 2014, the Criminal Justice Department began asking inmates entering the system whether they identify as transgender. Next began a three-month campaign to educate those already incarcerated, with prison and jail officials putting up posters and announcing through the offender newspaper that inmates could come forward at any time.

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Five months later, in August 2014, just 67 inmates identified as transgender, said department spokesman Jason Clark. Over the next year, that number more than tripled. The largest spike came between February and August 2015.

The population had continued to steadily rise since then, by 21 and 29 percent during the last two six-month periods, respectively.

Demoya Gordon, an attorney with the LGBT rights group Lambda Legal, said greater access to hormone therapy for Texas inmates could also help explain the increase.

"My suspicion it that it has to do with the hormone therapy change," she said. "People feel like they can finally get some treatment."

In August 2015, the department said it would expand access to hormone therapy for transgender inmates. Under the previous policy, inmates had to already be receiving hormones when they entered prison to be eligible to continue such therapy.

Now, some Texas inmates who are diagnosed with gender dysphoria — the feeling that your biological sex is contrary to your emotional and mental gender — can start hormone treatment for the first time while in prison.

TDCJ confirmed the number of transgender inmates receiving hormone therapy had increased since the policy changed from 21 in February of this year to 32 now, but Gordon that it's still very difficult for inmates to get the treatment.

"We continue to hear that while the policy exists on paper, it is still quite hard for many trans people to actually get the care they need in practice due to some TDCJ officials being very reluctant to refer people for gender dysphoria treatment," Gordon said.

Some advocates said they fear the spike in self-identifying inmates is due to more negative factors than an increased acceptance of transgender people.

Flor Bermudez, detention project director at the Transgender Law Center, said she worried that it could be explained by a spike in arrests of transgender people or because some transgender prisoners are fed up with current conditions and are now asking for special attention to avoid assault and violence.

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TDCJ's Clark said an additional 26 transgender inmates has been placed in "safekeeping," protective custody housing, in the last six months, but that the agency hasn't incurred any substantial additional costs since then related to the specialized treatment or housing of transgender inmates to date.

Bermudez said her organization now receives more letters from transgender inmates than ever. While the intentions behind the prison-rape law were good, she claimed it's had little impact on the ground.

"I have seen a trend of just more people who are transgender seeking remedy for all the violations they are subject to," said Bermudez. "Particularly on sexual violence, there is no improvement. If anything, things are getting worse."