Equal rights for the bilious, choleric, melancholic and sanguine!

Can a law prohibiting job discrimination itself be discriminatory? That’s the charge being leveled against a compromise version of the Employment Non-Discrimination Act, or ENDA, a bill in Congress that would add sexual orientation — but not gender identity — to the list of protected categories. Activists object that the compromise version of the bill, which congressional Democrats came up with under pressure from opponents of transgender rights, is itself discriminatory. But it’s an indictment that can be leveled against any civil-rights bill.

Let’s begin with ENDA. Fearing that the House wouldn’t vote for the bill if it included protection for transgendered people, Rep. Barney Frank (D-Mass.), after consulting with Speaker Nancy Pelosi (D-San Francisco), shunted the ban on gender-identity discrimination to a separate bill. Outrage ensued. In The Times’ Op-Ed page last week, Christine Daniels argued that Frank and Pelosi had committed the legislative equivalent of the “low bridge,” a basketball foul in which an opponent takes out a player’s legs as he or she leaps for a rebound, pass or jump shot.

But whether or not ENDA is re-revised to outlaw discrimination on the basis of gender identity, the bill will end up discriminating against some group. All anti-discrimination laws do, in the sense that they target some but not all of the characteristics that might lead a bigoted employer to fire — or refuse to hire — a qualified individual.

Firing, or not hiring, an employee because she is African American or Mormon or a woman exposes the employer to the full force of Title VII of the 1964 Civil Rights Act, which prohibits job discrimination on the basis of race, color, religion, sex or national origin. Firing an employee because he is over 40 triggers liability under the Age Discrimination in Employment Act of 1967. Discriminating against a handicapped employee invites legal action under the Americans with Disabilities Act of 1990.

Firing, or not hiring, someone because he is overweight, ugly, a “Star Wars” fanatic or a graduate of a non-Ivy League college is not illegal. Yet I have no doubt that members of these groups are the victims of at least occasional discrimination. If the Constitution guarantees equality under the law, why isn’t it unconstitutional for government to punish some acts of invidious discrimination but not others?

If that seems like a fantastic idea, consider that a majority of the Supreme Court flirted with it only 15 years ago. In R.A.V. v. St. Paul, the court unanimously invalidated the hate-crime conviction of a white teen-ager who burned a cross on the lawn of a black family.

According to Justice Antonin Scalia’s opinion, the law used against the boy was unconstitutional because it criminalized fighting words (and fighting symbols, like a burning cross) that aroused alarm “on the basis of race, color, creed, religion or gender.” This amounted to “viewpoint discrimination,” Scalia said, because the law didn’t punish words or gestures “designed to express hostility, for example, on the basis of political affiliation, union membership or homosexuality.”

Scalia’s opinion raised legal eyebrows — including those of his colleagues, several of whom disagreed with Scalia’s analysis while agreeing with the decision — because it seemed to point to a constitutional principle that all opinions were equal before the law, so that only the most general law against “fighting words” or acts of harassment could pass constitutional muster. From there it’s not a particularly slippery slope to the conclusion that Title VII, which bans job discrimination on the basis of gender but not sexual orientation, is “underinclusive” and thus unconstitutional. The best Congress could get away with would be a law against “wrongful termination” or “irrational discrimination.”

That nightmare scenario for civil-rights groups has receded because Scalia was unwilling, or unable, to push the court further in the direction of insisting on viewpoint neutrality in anti-discrimination laws. Why was it a nightmare scenario? Because a perfectly inclusive anti-discrimination law — one that gave the courts jurisdiction over every act of irrational bias by an employer — would be impossible to enforce. As a practical matter, Congress must pick and choose. Racial discrimination: actionable. Anti-state-college discrimination: not actionable.

These policy choices can be more or less deliberate — the inclusion of sex discrimination in Title VII has been described as an afterthought — but choices must be made. Race was chosen in 1964 because of the obvious magnitude of racial discrimination. Gender identity should be added because, even if the transgendered are a small minority, the prejudice against them is particularly nasty. But whatever the criteria for protecting victims of discrimination, some group is going to be left out. “Civil rights” does not mean “equal rights.”

Michael McGough is The Times’ senior editorial writer.

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