Look at statistics.
Fifty-three percent of transgender respondents to NTDS have been verbally harassed or treated disrespectfully in places of public accommodation, and 44 percent have been denied service because of their transgender identity.
Twenty-two percent of respondents who have interacted with law enforcement officers have been harassed by them, 20 percent have been refused assistance, 6 percent have been physically attacked by an officer, and 2 percent have been sexually assaulted by an officer. Transgender people of color faced higher rates of prejudice and violence, with up to 38 percent reporting harassment by officers.
Seventy-seven percent of transgender people have felt physically unsafe in public.
Twenty percent of transgender people have experienced discrimination in a social service agency, from both clients and staff.
On top of these high rates of discrimination and prejudice, transgender individuals also experience high rates of sexual violence. According to several studies, more than 50 percent have been sexually assaulted at some point in their lives.
In examining reports of hate crimes against transgender people, researchers found that 98% of all "transgender" violence was perpetrated specifically against people in the male to-female spectrum;
In the United States, an estimated 19.3% of women and 1.7% of men have been raped during their lifetimes; an estimated 1.6% of women reported that they were raped in the 12 months preceding the survey. The case count for men reporting rape in the preceding 12 months was too small to produce a statistically reliable prevalence estimate. An estimated 43.9% of women and 23.4% of men experienced other forms of sexual violence during their lifetimes, including being made to penetrate, sexual coercion, unwanted sexual contact, and noncontact unwanted sexual experiences. The percentages of women and men who experienced these other forms of sexual violence victimization in the 12 months preceding the survey were an estimated 5.5% and 5.1%, respectively.
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It looks like passability does help to some extent but its definitely not a silver bullet.
http://www.patheos.com/blogs/wwjtd/2012/05/murder-statistics-of-transgender-people/http://www.ovc.gov/pubs/forge/about_why.htmlhttp://www.cdc.gov/mmwr/preview/mmwrhtml/ss6308a1.htm