The former intelligence analyst is serving a 35-year prison sentence for passing classified U.S. government information to the anti-secrecy website WikiLeaks. Manning is serving the sentence at the Army prison on Fort Leavenworth in Kansas.
Leavenworth County District Judge David King said he'd allow the name change during a court hearing that lasted about a minute. Manning didn't attend the hearing but issued a statement saying it was "an exciting day."
"Hopefully today's name change, while so meaningful to me personally, can also raise awareness of the fact that we (transgender) people exist everywhere in America today, and that we have must jump through hurdles every day just for being who we are," Manning said.
The decision clears the way for official changes to Manning's military records, but it would not compel the military to treat Manning as a woman. That includes transferring Manning to a prison with a woman's unit.
The only impact of the district court ruling was changing Manning's name on military records, but not his confinement status, Army spokesman George Wright said.
"Likewise, the U.S. Disciplinary Barracks is a male-only facility and prisoners there are referred to by the title 'inmate'," Wright said in a statement to The Associated Press.
Manning, who grew up in Oklahoma, filed the court petition as the first step toward getting her Army records changed.
Manning has been diagnosed by at least two Army behavioral health specialists with gender dysphoria, or gender identity disorder.
Manning was sentenced in August for six Espionage Act violations and 14 other offenses for leaking more than 700,000 secret military and U.S. State Department documents, along with battlefield video, while working as an intelligence analyst in Iraq in 2009 and 2010. An Army general upheld the convictions last week, clearing the way for appeals with the Army Court of Criminal Appeals.
There was no opposition filed to the petition, though Manning included several newspaper reports indicating the desire to live publicly as a woman last August, as well as copy of an Oklahoma birth certificate.
She has filed a grievance with the U.S. Disciplinary Barracks commander at Fort Leavenworth over the lack of a response to her request for comprehensive treatment for her gender identity disorder, including specialized gender counseling and hormone replacement therapy.
The military has said it doesn't provide hormone replacement therapy. Gender dysphoria generally disqualifies one for military service, but Manning can't be discharged while serving the prison sentence.
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