Blogger Amber points to the tale of a transsexual survivor of Katrina being arrested for using the woman’s room and asks “Why not have unisex bathrooms?” One obvious reason is that, in commercial establishments at least, unisex restrooms present a stronger risk of alienating customers with a preference for the single-sex model than vice versa. Still, social mores have changed in some places, and the architecture hasn’t caught up.
Here, I suspect there are liability-related reasons. The first innovator to create a unisex bathroom and be unfortunate enough to be the scene of a sexual assault in the bathroom is going to be sued for not conforming to the standard practice. So there’s a collective action problem even to the extent that institutions wish to create unisex restrooms. (The uber-trendy bar and restaurant Mie N Yu in Georgetown has a unisex bathroom, but they have a full-time attendant.)
It is worth noting that single-sex restrooms have an evidentiary advantage over the unisex model. In the scenario of a man who uses the restroom to commit a sex crime against a woman (be it indecent exposure or peeping tomism or worse), it’s a lot easier to presume that the man is up to no good if he is in a woman’s restroom than if he is in a unisex restroom; a perpetrator can plausibly claim a misunderstanding. In economic terms, the expected “cost” of committing the sex crime would decrease. One would thus predict that sex crimes would be more common in unisex restrooms than single-sex restrooms.