SAN FRANCISCO (CBS/AP) — An independent commission led by a former U.S. surgeon general has concluded there “is no compelling medical reason” for the U.S. armed forces to prohibit transgender Americans from serving and that President Barack Obama could lift the decades-old ban without approval from Congress, according to a report being released Thursday.

The report said Department of Defense regulations designed to keep transgender people from joining or remaining in the military on the grounds of psychological and physical unfitness are based on outdated beliefs that require thousands of current service members either to leave the service or to forego the medical procedures and other changes that could align their bodies and gender identities.

“We determined not only that there is no compelling medical reason for the ban, but also that the ban itself is an expensive, damaging and unfair barrier to health care access for the approximately 15,450 transgender personnel who serve currently in the active, Guard and reserve components,” said the commission led by Dr. Joycelyn Elders, who served as surgeon general during Bill Clinton’s first term as president, and Rear Adm. Alan Steinman, a former chief health and safety director for the Coast Guard.

The panel, convened by a think tank at San Francisco State University, said the ban has existed for several decades and apparently was derived in part from the psychiatric establishment’s consensus, since revised, that gender identity issues amounted to a mental disorder.

The ban also appears based on the assumption that providing hormone treatment and sex reassignment surgeries would be too difficult, disruptive and expensive. But the commission rejected those notions as inconsistent with modern medical practice and the scope of health care services routinely provided to non-transgender military personnel.

“I hope their takeaway will be we should evaluate every one of our people on the basis of their ability and what they can do, and if they have a condition we can treat we would treat it like we would treat anyone else,” Elders said in an interview with The Associated Press, which was provided along with the report ahead of official release.

At least a dozen nations, including Australia, Canada, England and Israel, allow military service by transgender individuals. Transgender rights advocates have been lobbying the Pentagon to revisit the blanket ban in the U.S. since Congress in 2010 repealed the law that barred gay, lesbian and bisexual individuals from openly serving in the military

“At this time there are no plans to change the department’s policy and regulations which do not allow transgender individuals to serve in the U.S. military,” said Navy Lt. Cmdr. Nate Christensen, a defense department spokesman.

The commission argued that facilitating gender transitions “would place almost no burden on the military,” adding that a relatively small number of active and reserve service members would elect to undergo transition-related surgeries and that only a fraction might suffer complications that would prevent them from serving. It estimated that 230 transgender people a year would seek such surgery at an average cost of about $30,000.

Retired Brigadier General Thomas Kolditz, a former Army commander and West Point professor on the commission, said he thinks allowing transgender people to serve openly would reduce gender-based harassment, assaults and suicides while enhancing national security.

“When you closet someone, you create a security risk, and we don’t need another Chelsea Manning,” Kolditz said, referring to the soldier formerly known as Bradley Manning who came out as transgender after being sentenced for leaking classified documents to the website WikiLeaks.

But Center for Military Readiness President Elaine Donnelly, whose group opposed the repeal of the ban on openly gay troops, predicted that putting transgender people in barracks, showers and other sex-segregated could cause sexual assaults to increase and infringe on the privacy of non-transgender personnel.

“This is putting an extra burden on men and women in the military that they certainly don’t need and they don’t deserve,” Donnelly said.

The commission recommends the president issue an executive order instructing the Department of Defense to amend its regulations so transgender people are no longer automatically barred. The Pentagon then would need to develop rules for assigning service members who are transitioning, said Palm Center Executive Director Aaron Belkin, whose San Francisco State-based think tank commissioned the report.

The Palm Center, which previously researched “don’t ask, don’t tell,” is funded in part by a $1.3 million grant from Jennifer Pritzker, a billionaire former Army lieutenant colonel who came out as transgender last year.

The Williams Institute, a think-tank based at UCLA, estimates about 15,500 transgender personnel are currently serving, nearly all under their birth genders and not transitioning in an appearance-altering way.

Army Reserve Capt. Sage Fox, 41, was one until recently. Following a deployment to Kuwait, Fox started taking female hormones last year. In November, with her hair getting long and her voice higher, she notified her battalion commander, whom she says expressed support. At drill time, an announcement was made to 400 colleagues at the B.T. Collins Reserve Center in Sacramento.

For a few days, Fox thought she might escape the ban. But then she was informed she had been placed on inactive status.

“When I transitioned, I wasn’t just a good officer, I became a better officer because I didn’t have to deal with that conflict anymore,” she said.

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