US District Judge Colleen Kollar-Kotelly ordered the government to “revert to the status quo” that was in effect before Trump ordered the contentious ban.

At the same time, however, she allowed to let stand a block on military funding for sex reassignment surgery for members of the armed forces.

Trump’s predecessor Barack Obama took the historic decision to allow openly transgender troops to serve in the military, a move that was due to go into full effect in July this year.

The new administration announced in June a six-month delay on implementing that ruling. In July, Trump surprised Pentagon leaders by announcing on Twitter a ban on transgender people serving in the armed forces.

“After consultation with my Generals and military experts, please be advised that the United States Government will not accept or allow Transgender individuals to serve in any capacity in the U.S. Military,” Trump tweeted.

“Our military must be focused on decisive and overwhelming victory and cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail.”

In her ruling, Kollar-Kotelly took issue with Trump’s claims.

“The Department of Defense Working Group, made up of senior uniformed officers and senior civilian officers from each military department, unanimously concluded that there were no barriers that should prevent transgender individuals from serving in the military,” the judge said.

“In short, the military concerns purportedly underlying the president’s decision had been studied and rejected by the military itself.”

Ruling welcomed by rights groups
Trump signed a document in late August ordering the Pentagon to no longer enlist transgender recruits but leaving it to decide the fate of those already serving.

The president also barred federal funds from being used to cover the costs of medical treatment associated with gender reassignment surgery of troops already serving.

He gave the Pentagon until March 23, 2018 to craft a new policy on transgender service members.

The lawsuit against the president’s order was filed by five transgender service members in August, citing the uncertainty that surrounded their future careers.

Estimates about the number of transgender people serving in the US military vary from 1,320 up to 15,000, out of 1.5 million active duty troops.

An attorney for the American Civil Liberties Union, which is battling the ban, predicted that Trump’s moves would face further legal opposition.

“This is the first decision striking down President Trump’s ban, but it won’t be the last,” ACLU senior staff attorney Joshua Block said in a statement.

“The federal courts are recognizing what everyone already knows to be true: President Trump’s impulsive decision to ban transgender people from serving in the military service was blatantly unconstitutional,” Block said.

“We will continue to work to ensure that transgender service members are treated with the equal treatment they deserve.”

The ACLU has filed a separate lawsuit arguing that Trump’s ban violates the constitutional guarantee of equal protection by authorizing discriminatory treatment.

Human Rights Campaign, an LGBT advocacy group, welcomed the judge’s ruling, which is expected to be appealed by the Trump administration.

“Today’s preliminary injunction is an important step in the ongoing efforts to protect transgender service members from the dangerous and discriminatory policies of Donald Trump,” HRC legal director Sarah Warbelow said in a statement.

“Donald Trump’s erratic tweets and half-baked orders disrespect the bravery of the countless transgender people who have fought, and in many cases died, for their country,” Warbelow said.

“We are grateful that a federal judge has blocked this administration from discharging any qualified individuals because of their gender identity while these cases continue to make their way through the courts.”