The Supreme Court voted 5–4 Tuesday to enact the Trump administration's policy prohibiting people with a gender identity that differs from their biological sex from serving in the military, while cases challenging the ban continue in lower courts.
The ban excludes those who are already serving in the military and those who are willing to serve "in their biological sex," but anyone wishing to transition during their service will risk discharge.
The transgender military ban simplifies the concept of sex, which, according to research, is not as binary as the Trump administration thinks it is. A person's sex is much more complicated than having XX or XY chromosomes and the corresponding genitalia. As Emma Sarappo reported for Pacific Standard:
All in all, there are five interconnected factors that indicate an individual's sex: gonads, hormones, internal reproductive organs, chromosomes, and external genitalia. These typically align with one another and with a person's secondary sex characteristics (hair growth, voice pitch, fat distribution, and all the other little signs we think of as male or female). But often, they don't, in ways that sometimes aren't discovered until a person tries to have children or has an unrelated health problem. And the percentage of the population this affects is not insignificant: Maybe as many as 2 percent of live births have intersex traits—close to how many people have the blood type B negative.
A 2017 study published in the American Journal of Public Health estimated there are around one million transgender people in the United States. What's more, a 2013 study by the Williams Institute at the University of California–Los Angeles found that transgender people are more than twice as likely to serve in the military as the general population. So this ban prevents a significant portion of the U.S. population from serving the country—and one that has reliably proven its willingness to serve.
President Donald Trump tweeted his justification for the ban, saying transgender soldiers burden the military with "tremendous medical costs and disruption." But the RAND corporation issued a report in 2016 finding that allowing transgender people to serve in the military would have a "minimal impact on readiness and health-care costs." As Susannah Rodrigue reported for Pacific Standard in 2017:
Researchers estimated that "10 to 130 active component members each year could have reduced deployability as a result of gender transition-related treatments." In terms of health-care costs, "the study estimated that between 30 and 140 new hormone treatments could be initiated a year and 25 to 130 transition-related surgeries could be utilized a year among active component service members. Additional health-care costs could range between $2.4 million and $8.4 million, representing an approximate 0.13-percent increase."
To put those numbers in context, the Military Times reported that the Department of Defense spent $84 million on erectile dysfunction medications in 2014.