Note: The original version of this piece stated in error that the Idaho Supreme Court issued the opinion against Melissa Nelson. It was the Iowa Supreme Court.

When my family celebrated my bar mitzvah and my twin sister’s bat mitzvah, we followed the fairly common practice of having a party at a catering hall, which also held events for weddings and other festivities. As part of the marketing program for the venue, clients were offered a free vocalist if they chose a house band. We observed the groups, heard the separate singer’s able skills and accepted the hall’s offer. The singer was an attractive woman. (The band was all male.) When the day of our grand fete arrived, the band members had not changed, but the bonus singer had been replaced by a perfectly capable man. When we curiously asked what had happened to the original singer who was offered as part of the package deal, the business manager rather quickly responded that the contract only provided for a bonus singer — not any specific individual. We actually didn’t care who was performing, but were merely showing concern for the absent performer. We later discovered that the female soloist had been — according to her former employer — replaced because too many brides were displeased with her presence at their weddings due to her sex appeal. At the age of 13, I found this phenomenon troubling. I still do.

Studies have shown that attractive people, on the whole, benefit from their good looks well beyond the obvious. All else being equal, they are more likely to get jobs and make higher salaries. Under what psychologists have labeled the "halo effect," people generally assume that the physically attractive also possess other positive traits, such as trustworthiness, benevolence and brainpower. Indeed, attractive defendants have been found to do better with juries, and taller presidential candidates generally win the popular vote. But, as already described, good looks are not always all that they are cracked up to be.

Recently, 32-year-old Melissa Nelson was fired, after 10 years of employment, by her 53-year-old employer, James Knight — a dentist. When the dentist’s wife, "Jeanne Knight[,] found out that her husband and Nelson were texting each other…Jeanne Knight confronted her husband and demanded that he terminate Nelson’s employment.…Dr. Knight [said] that Melissa Nelson had not done anything wrong or inappropriate and that she was the best dental assistant he ever had."

Nelson sued under Iowa’s state discrimination statute, which is quite similar to the federal statute, and lost. The state Supreme Court ruled that Nelson was fired due to romantic jealousy, not discrimination. The decision would only be bad policy had the outcome properly flowed from the law. But here the conclusion was poor interpretation by the Iowa high court.

The tribunal noted that the employer had all female employees and that Knight replaced Nelson with another woman. This is evidence that Knight didn’t discriminate against all women, but it is not evidence that he doesn’t discriminate against some. It seems relatively simple to acknowledge that Knight was motivated by a combination of two factors: sex (some say, gender) and beauty. This is not a novel concept. "Sex plus" discrimination has been recognized by various courts, including the U.S. Supreme Court. Knight would not have acted had not both elements been present — nor seemingly would his wife (or the brides celebrating at the catering hall described above) have been troubled had the eye-catching female employee been a spectacularly striking man. The jealousy about which the defendant and his wife were concerned is very much linked to the sex of the plaintiff. And employment decisions based upon the sex of the employee are illegal under current law.

Moreover, what if Knight had fired Nelson because she was female and, say, black? Now, neither factor would be the sole motivating factor, but the combination would be. True, in this hypothetical both factors are bases for a cause of action. But why should a would-be defendant be able to shield his otherwise wrongful action because he has watered it down with a wholly permissible, albeit equally as unimpressive, basis for terminating employment? I certainly could envision requiring that the impermissible basis be a significant factor for the law to be implicated — but demanding, essentially, that it be the sole factor is legally and philosophically untenable. Indeed, the text of the statute provides no such restriction. And the history of Title VII of the Civil Rights Act of 1964 is intriguing on this very issue: Sex was only added to the bill as an illegal basis for employment decisions just prior to its passage in a last-ditch effort to defeat the overall measure. Adversaries of the law had hoped that middle-of-the-roaders would be concerned about broadly mandating sex equality in contexts such as the military. The effort backfired, and left an even more expansive law — with the provision on sex discrimination as pure text devoid of any significant legislative history.

The law often swings between underinclusiveness and over — what statisticians note as type one and two errors. Here we see an example of the former. Luckily, courts are only the final word retrospectively. Legislatures are perfectly able to revise misinterpreted laws so as to prevent future injustices based on the errors or ignorance of courts. This seems one such opportunity.

Robert Steinbuch is a law professor at the University of Arkansas at Little Rock William H. Bowen School of Law.