ITHACA, N.Y. -- Public single-sex schools, once thought out of step, are returning -- promoted by an unlikely coalition of progressive and conservative groups.

Communities need to know whether these schools are constitutional -- as well as whether they are good for young people, says Cornell University Law Professor Gary Simson.

Simson looks at the issue of separate public schools for girls and boys through the lens of the landmark 1954 Supreme Court ruling in Brown v. Board of Education , which stated that when it comes to race, separate cannot be equal. "Are sexually separate schools, like racially separated schools, inherently unequal?" Simson asks in an article in the Cornell Law Review . The issue is one that the Supreme Court has yet to resolve, he noted.

The issue is especially relevant today because "public single-sex schools, which had almost disappeared from the scene in the United States 15 years ago, began to make a comeback in the early 1990s," Simson writes. Their return owes much to reports, such as one by the American Association of University Women, showing gender bias in the schools and to a push from the administration of President George W. Bush authorizing special funds for public single-sex schools and amendments to Title IX regulations that impede them.

Simson discusses how the courts have viewed the separate-but-equal claim for single-sex schools, how they should see it and why promoters of single-sex schools may be wrong about the benefits.

In 1974 Susan Vorchheimer, an honors graduate of a Philadelphia junior high school, sued, under the U.S. Constitution's equal protection clause, to be admitted to a prestigious all-boys public high school in Philadelphia. Under school district policy, Vorchheimer could have attended a highly regarded all-girls public high school or a less-competitive coeducational school. After her application to the all-boys school was rejected, a lower court ordered her admission. But the Federal Appeals Court for the Third Circuit reversed the decision, finding the all-girls and all boys schools separate but essentially equal -- although it conceded the science facilities at the boys school were "superior."

The case went to the U.S. Supreme Court, where, with Chief Justice William Rehnquist not participating, the justices split evenly; four of them voted to overturn the Third Circuit decision and four voted to let the decision stand. With the Supreme Court issuing no written opinions, the Third Circuit decision that kept Vorchheimer out of the boys school was left standing.

Citing other relevant cases, Simson provides a framework for answering the question in the Vorchheimer case that the high court deadlocked on 28 years ago but eventually will need to answer: Are single-sex public schools inherently unequal and thus, unconstitutional? He asks whether coordinate single-sex public schools -- an all-boys school and an all-girls school in the same community -- disadvantage girls. And he offers questions a court might ask, were the case being heard today: "In a society in which gender stereotyping is hardly a thing of the past, do coordinate single-sex schools send a message that girls and boys are best kept separate because girls cannot compete effectively with boys? Even if the all-girls school is no less rigorous and competitive than the all-boys school, will the girls' accomplishments at their school be undervalued by college admissions officers, employers and others because of preconceived notions about all-girls schools, as compared to all-boys schools?" Relying in part on sociological studies, Simson questions the force of various arguments made for single-sex education: that it is less distracting for students; that it provides academic and developmental benefits for both sexes that could not be achieved in coed schools; and that it enhances the diversity of options available to parents and children.

Simson also considers in detail the constitutionality of public single-sex education when it takes a form that, on its face, advantages girls: giving girls the option of attending a coed or single-sex public school while only allowing boys to attend a coed one. In that context, as in that of coordinate schools, Simson maintains that the question of constitutionality should turn on whether girls are disadvantaged in some significant respect. He points out, for example, that creating single-sex schools only for girls risks sending "a message to both girls and boys that girls are in some sense inferior to boys -- whether that means more needy, less adaptable, more fragile or some other disempowering comparative generalization."

Finally, Simson cautions: "Even if public single-sex schools pass constitutional muster, they represent too limited a response to the gender equity problems that sparked renewed interest in public single-sex education in recent years." In his view, if school districts are "really serious" about solving those problems, they "need to tackle them head-on by changing the practices and atmosphere in coed schools."

Simson's paper was published in the Cornell Law Review , Vol. 90, No. 2, January 2005. It is accessible at http://papers.ssrn.com/paper.taf?abstract id=646961 .