The discussion of accommodating patient modesty-based preferences (see this post about the cervical smear test and the transgender nurse) led me to a hypothetical that I thought I'd raise. I realize that it's unusual, and may be on one end of the spectrum of when gender should matter; but like many possible edge cases, it can help us think through other cases as well, and decide which ones (if any) are analogous to it. I'd especially like to hear from people who would generally come down on the transgender rights side of the debate in most other employment contexts.

Let's assume a country or state in which brothel prostitution is legal (as it is in some Nevada counties and in some European countries). And let's assume a brothel that caters to many sexual orientations, and as a result has both male and female prostitutes working in it. (I'm not sure whether brothels do indeed follow this business model, but say that they do.) Finally, let's assume that street prostitution and even online direct-contact prostitute hiring is still illegal, so the brothels are the only game in town.

A gay man comes to the brothel, and says "I'd like a man to perform oral sex on me"; he's not picky about the man. They go to the room and start to get down to business—but the gay man realizes that the man is physically a woman. (Perhaps the prostitute strips down, and the situation becomes evident, or the customer feels something unexpected during foreplay, or the customer just recognizes that this is someone who he has heard is transgender; assume there's no doubt about the physical fact.) "Wait, I asked for a man!," the customer says. "I am a man," the prostitute says; "I self-identify as a man. And what do you care about whether I have a penis? You're just asking me for oral sex." "I don't care how you self-identify," the customer says, "I want someone who is physically a man, even if I'm not going to be touching his genitals." The customer leaves (without paying) and complains to the brothel.

What do you think is the sound answer here?

A. The brothel operator should be legally forbidden from assigning prostitutes based on sex at all, at least when it comes to oral sex. The patron's desire for a prostitute of a particular sex is not rational—the physical act, after all, is the same regardless of the performing party's sex. And such customer preferences, including nonrational ones, can't justify gender identity discrimination in employment. (To be sure, unlike the man in our hypothetical, customers of brothels often care about other aspects of a prostitute's physical appearance, and most physical appearance discrimination is not illegal, at least in most places in the U.S.; but the point of gender identity discrimination law is in part to bar discrimination based on certain aspects of physical appearance.)

B. The brothel operator should be legally free to assign prostitutes based on sex, but the prostitute's self-identified sex is all that can matter. Once the objecting customer hears from the prostitute, "I self-identify as a man," that should be enough for the customer. (Again, we're talking about a sex act that's physically identical regardless of the prostitute's genital equipment.)

C. The brothel operator should be legally free to assign prostitutes based on sex as the customer understands the sex. If the customer says, "No, I want to have oral sex performed on me by someone who has a penis, even if I don't actually touch the penis during the act," then the brothel operator should be free to accommodate that.

It seems to me pretty clear that the answer is (C)—that while human sexual reactions may not be rational, they are legitimate features of people's preferences that merit accommodating, even in a regime that generally bans sex discrimination and that requires businesses to treat most employees based on their self-identification. Indeed, because the choice about whom to have sex with is such an intimate choice, even when done commercially and on a one-time basis, it would be wrong for the law to stop a customer from having this choice, at least once prostitution is generally legalized. (I recognize, by the way, that some customers may prefer to have sex with transgender people; I'm only focusing here on those who don't.)

Now if you agree with me about that, then the question is how far this analogy goes. A few options:

[1.] It doesn't extend at all beyond this hypothetical, because sexual contact is different—the only place where it's legitimate to care about the physical genital equipment of the person you're having sex with. (Perhaps your view might be that sexual arousal is nonrational but can be taken as a biological given, which we should accept rather than trying to change, but that sexual modesty ought to be fought; if so, would it matter if the patron is bisexual, and could be aroused by someone he perceives as a woman, but just happens to right now want someone he perceives as a man?)

[2.] It does extend at least to medical tests that involve genital contact—a person should be free to decide whether it's a man or woman touching the person's genitals, and should be free to focus on perceived physical attributes and not just self-identification in deciding that gender—and that's true whether the underlying nonrational concern has to do with sexual stimulation or with sexual modesty.

[3.] It extends to all situations where sex discrimination is generally allowed, for instance where the job involves seeing people naked; once we conclude that sex is a bona fide occupational qualification for a particular job, the exemption from the ban on sex discrimination should also apply to the ban on gender identity discrimination.

[4.] No need for the analogy; you think it's fine to stymie would-be sex buyers' sexual pleasure by rigidly enforcing antidiscrimination law, but you think it's not fine to stymie people's privacy preferences, when it comes to medically necessary procedures.

[5.] No need for the analogy; you think gender identity discrimination should generally be permissible even if sex discrimination is not.

Just to anticipate a possible reaction, of course I recognize that many people view prostitution as immoral, entirely apart from the gender questions raised here, and that very few view medical genital exams as immoral. But I'm not trying to draw an analogy between the moral status of the underlying actions—I'm trying to draw an analogy between nonrational preferences (whether related to privacy/modesty or to sexual pleasure) when it comes to deciding who touches one's genitals. And, finally, of course I'm not claiming that transgender people are any more likely to be prostitutes (or for that matter nurses); I'm just asking what should happen in a case where a prostitute is indeed transgender.