WASHINGTON  In an unusual show of support for allowing gay men and lesbians to serve openly in the armed forces, an article in an official military journal argues forcefully for repealing the “don’t ask, don’t tell” law, which requires homosexuals in the services to keep their sexual orientation secret.

The article, which appears in Joint Force Quarterly and was reviewed before publication by the office of Adm. Mike Mullen, the chairman of the Joint Chiefs of Staff, says that “after a careful examination, there is no scientific evidence to support the claim that unit cohesion will be negatively affected if homosexuals serve openly.”

Although the article, by an Air Force colonel, Om Prakash, carries no weight as a matter of policy, it may well signal a shift in the official winds. It won the 2009 Secretary of Defense National Security Essay competition.

Colonel Prakash, who researched the issue while a student at the National Defense University, in Washington, and who now works in the Pentagon, concludes that “it is not time for the administration to re-examine the issue.” Instead, he writes, “it is time for the administration to examine how to implement the repeal of the ban.”