WASHINGTON -- A report led by four retired military officers suggests Congress should repeal the "don't ask, don't tell" policy for gays in the U.S. military.

"Evidence shows that allowing gays and lesbians to serve openly is unlikely to pose any significant risk to morale, good order, discipline, or cohesion," the study said.

It also found that the law has forced some commanders to choose between breaking the law and undermining the cohesion of their units, and has prevented some gay, lesbian, and bisexual service members from obtaining psychological and medical care and religious counseling.

The law has also caused the military to lose some talented service members, and has made it harder for some gays, lesbians, and bisexuals to perform their duties, the study said.

The four retired officers leading the study were Marine Brig. Gen. Hugh Aitken, Air Force Lt. Gen. Minter Alexander, Army Lt. Gen. Robert Gard and Navy Vice Adm. Jack Shanahan. The Michael D. Palm Center at the University of California at Santa Barbara, a public policy think tank, sponsored the research. Read the full report here.

The report pointed to the British and Israeli militaries, where it said gay people serve openly without hurting the effectiveness of combat operations.

The issue of gays in the military has played a part in recent presidential elections, and in the current race, after former President Bill Clinton signed the current "Don't Ask, Don't Tell" policy into law in 1993. Prior to that, gays were not allowed to serve.

Republican John McCain says he supports the current law. Democrat Barack Obama wants the law repealed.

In general, the law says that gay men and women may serve in the U.S. military as long as they keep their sexuality a secret. It also prohibits commanders from investigating a service member's sexuality. The military may punish service members who engage in open homosexual behavior. More often than not, punishment means being thrown out of the military.

In November 2007, citing statistics that indicated roughly 65,000 gays served in the military, 28 retired generals and admirals urged Congress to repeal the law and allow gays to serve openly. The most prominent among those making the request was retired Gen. John M. Shalikashvili, who was chairman of the Joint Chiefs of Staff when the policy was adopted.

In January of that year, Shalikashvili wrote in a New York Times op-ed column, "I now believe that if gay men and lesbians served openly in the United States military, they would not undermine the efficacy of the armed forces."

"We must welcome the service of any American who is willing and able to do the job," he said.