In May 1944, Lemuel S. Brown, a lieutenant in the U.S. Army during World War II, received a blue slip of paper from the military, notifying him he was being dismissed from duty. The reason? “Undesirable” behavior—specifically, an accusation of “attempting to perpetrate an act of Homosexuality,” as he explained in a letter to the National Association for the Advancement of Colored People, from whom he was seeking legal help. He wanted to fight his so-called “blue discharge,” since receiving it carried a powerful stigma and serious negative consequences for his future.

During World War II, Brown was one of nearly 50,000 U.S. Army soldiers, according to a 1946 War Department estimate, who received a blue discharge dismissing them from the armed services. Rarely backed by any formal procedure or inquiry, these notices facilitated the removal of thousands of queer people, African Americans, people with mental illnesses, alcohol or substance issues, bed-wetters and anyone else the military classified as “undesirable.” A code in the top corner of the notice explained the reason for the discharge—“HS,” for instance, meant the person was considered a homosexual.

Existing in a limbo between an “honorable” and “dishonorable” termination, blue discharges profoundly derailed the lives of queer World War II veterans for decades to come. Those marked with an “HS” essentially outed recipients at a time when sodomy was still a felony in every state, precluding many from returning to homes and communities likely to shun them. It raised alarm bells for potential employers, derailing future careers. And it barred recipients from receiving benefits from the G.I. Bill, the government program that gave veterans generous funding for college tuition, home and business loans, and unemployment insurance, crucial stepping stones to financial and social stability.

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For the first 100 years of its existence, the U.S. military relied on a two-pronged discharge system. Service members who left the military could receive either an “honorable” or “dishonorable” release. Outright dishonorable discharges were rare, however, because they required a court-martial trial.

At the end of the 19th century, the U.S. military began expanding its menu of options. It added a Without Honor discharge in 1893, followed by an Unclassified discharge in 1913. Both could be issued without a court-martial hearing, and because they were both printed on blue paper, they together became known as “blue discharges.” With WWII’s massive human mobilization, the military shifted from its practice of jailing soldiers accused of homosexuality (which required time-consuming, expensive court-martials) to simply deeming them psychologically unfit. Blue discharges could be dispensed to anyone with “undesirable traits of character,” a term ultimately applied in large numbers to queer people.

While the discharges affected people of all races, it took a particularly heavy toll on Black soldiers, University of Michigan historian Jennifer Dominique Jones told HISTORY.com. In her 2016 paper on the impact of blue discharges on Black queer service members, Jones wrote that Black soldiers, who were more likely to be scrutinized, discriminated against and given more extreme punishments for relatively minor infractions, received 22 percent of all blue discharges, more than double their proportional share of the military at the time.

According to Jones, the NAACP worked with Black service members accused of homosexuality, like Lemuel Brown, to appeal to the Discharge Review Board for a changed status—usually with little success. For these veterans, already facing formidable racist barriers to jobs and housing, the stain of a blue discharge further crippled their future prospects for chances for stability.

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In their effort to screen out queer conscripts, military officials ran into a problem: They didn’t have a conclusive way of identifying them, beyond a set of subjectively interpreted “signs” such as “feminine bodily characteristics” and “effeminacy in dress and manner,” according to Allan Bérubé, author of Coming Out Under Fire: Gay Men and Women During World War II. During World War II, out of some 18 million potential enlistees, the military only identified between 4,000 and 5,000 homosexuals, a severe undercount, estimates Bérubé.

Military scientists began devising dubious tests to measure sexual orientation. In 1944, according to Bérubé, an Army doctor tested tongue depressors on patients who were being treated as “sexual psychopaths”—one of the code terms for homosexuals. Their conclusion: 89 percent of homosexual patients who had performed oral sex in the past didn’t have a gag reflex. The doctor proclaimed that a tongue depressor test could screen out gay people not just from military service, but from other federal agencies as well.

Other doctors began exploring whether they could diagnose homosexuality—through Rorschach tests or by measuring sexuality through hormone tests. (One Army psychiatrist theorized that homosexual men would show higher levels of estrogen than testosterone—and lesbians the reverse.) None of these theories panned out.

In part because of the difficulties of scientifically measuring queerness, the War Department in January 1944 began to allow discharges on the basis of “latent homosexuality.” That gave officials license to eject someone for homosexuality under the blue discharge system simply because they seemed gay—even if the military lacked proof.

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In October 1945, the Pittsburgh Courier, a leading Black newspaper, published an article that accused the U.S. military of handing out blue discharges due to racial prejudice.

The report sparked an investigation by a seven-member special committee from the House Committee on Military Affairs. In January 1946, the committee published a report lambasting the blue discharge system as over-used and for bringing long-lasting discrimination on its victims. When veterans were forced to show their blue discharge to potential employers, companies assumed “that there is something radically wrong with the man in question,” the report stated, or that they committed an act “so mysterious that it cannot be talked about or written down, but must be left to the imagination.” Blue discharges, in other words, created cascading discrimination that haunted the job prospects of ex-service members for decades to come.

The report also criticized the Veterans Administration for blocking homosexuals from receiving G.I. benefits, insisting the agency should not be in the business of “passing moral verdicts on the history of any soldier.”

For a brief moment, the House Committee on Military Affairs report seemed to promise real reform. Between late 1945 through 1947, soldiers removed from the armed forces for homosexuality received discharges under honorable conditions, making them eligible for G.I. benefits. But the policy wasn’t retroactive, meaning that thousands who had already received a blue discharge for homosexuality were still denied benefits. And at the end of 1947, the military reverted back to dismissing homosexuals under ambiguously honorable conditions. Instead of “blue discharges,” it labeled them simply “other than honorable discharges.”

The Cold War ushered in a new gay panic, reversing those reforms. In 1950, as Senator Joseph McCarthy stirred fears of Communist infiltration in the U.S., he focused on queer people as a cause for concern, suggesting that their often closeted secret made them susceptible to blackmail by foreign enemies. In 1953, Dwight Eisenhower signed Executive Order 10450, which required the federal government to fire queer people. What followed came to be known as the “lavender scare,” during which thousands of queer workers were driven out of their U.S. government jobs.

In this increasingly hostile climate, soldiers who had received blue discharges for homosexuality had their hopes for reform dashed. And the military continued giving them. In total, between World War II and 2011, when the military’s “Don’t Ask, Don’t Tell” law was repealed, at least 100,000 more soldiers were removed for homosexuality. Among them was Harvey Milk, a Korean War veteran who went on to become the first openly gay political official in the United States.

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