The Williams Institute, at UCLA's School of Law, focuses on sexual orientation and gender identity law and public policy. The full report is here (PDF). It explains the scientific methodology, and offers this conclusion:
Many transgender people desire to serve their country in the armed forces, yet are not allowed entry or allowed to remain in the service if they wish to live their lives true to their gender identities. Transgender service members and veterans have reported wide-ranging experiences of discrimination, harassment, and physical and sexual assault while serving in the military. Outside of the military, transgender veterans in the NTDS experienced higher rates of homelessness, incarceration, and family rejection than those who did not serve. Transgender veterans described unique challenges and barriers to obtaining necessary health care and accurate identification documents. The repeal of “Don’t Ask, Don’t Tell” does not provide a public policy solution for these problems transgender service members and veterans experience. Though the VHA has begun to address transgender veterans’ health care concerns, it will be necessary to make additional changes to military policies in order to allow transgender people to serve openly and with honor.
As Maggie blogged yesterday, the Kinsey Institute just got funding to do research on the lives of trans people in the military. It's good to see more attention paid.