Just when I think religious liberty is alive and well in public schools, a school district does something bizarre to give the First Amendment a bad name.

The latest poster-case for misbegotten efforts to turn public schools into religion-free zones comes out of Everett, Wash., where school officials barred students from playing an instrumental version of “Ave Maria” at graduation in 2006.

Although the senior members of the wind ensemble have been allowed each year to choose what to play at graduation, this time they were told not to perform “Ave Maria” because “musical selections for all graduations within the district should be purely secular in nature.” Some audience members, the school explained, might be offended by the religious connotations of “Ave Maria” — Latin for “Hail, Mary.”

One student musician sued, charging the school with violating her freedom of speech. First the district court and then the 9th U.S. Circuit Court of Appeals sided with the school district. According to the three-judge panel of the appeals court, “it is reasonable for a school official to prohibit the performance of an obviously religious piece.”

Notice that the court’s ruling doesn’t say public schools must ban all religious music from performances. Instead, the court defers to administrators who worry that allowing such music might give the appearance of school endorsement of religion in violation of the First Amendment’s establishment clause.

On March 22, the U.S. Supreme Court refused to hear the case, Nurre v. Whitehead, thus sending a message to school officials (at least in the Western states covered by the 9th Circuit) that they have broad authority to ban any and all student expression that touches on religion at school events.

Justice Samuel A. Alito Jr., however, wrote a strong dissent, arguing that “a decision with such potentially broad and troubling implications merits our review.” According to Alito, Supreme Court precedents make it clear that “discrimination against religious, as opposed to secular, expression is viewpoint discrimination.”

Alito’s First Amendment concern in this case wasn’t with school endorsement of religion, but rather with school suppression of free speech. “When a public school purports to allow students to express themselves,” he writes, “it must respect the students’ free speech rights.”

School districts often justify censorship of student speech, as this one did, on the grounds that someone in the audience might be offended. But as Alito points out, the Supreme Court has rejected “the proposition that speech may be censored simply because some in the audience may find that speech distasteful.”

The tricky part, of course, is figuring out where to draw the line on student speech at a school-sponsored event, especially when students are given choices about what they can say (or play, in this case). Alito would no doubt agree that school officials need to retain some control in case the student veers off into the realm of speech inappropriate for a school setting, including speech that proselytizes or attempts to involve the audience in a religious exercise.

But just because line-drawing is difficult doesn’t mean the courts should give school officials carte blanche to censor all student references to religion at school events. Surely a way can be found to allow students to express personal religious views — or play instrumental music with religious associations — without sending a message of school endorsement of religion.

What’s most troubling about this case is the sweeping nature of the 9th Circuit’s opinion in support of the school district. If schools have the authority to bar student references to religion, then presumably they have the power to ban any and all student speech that some member of the audience might find offensive or controversial.

Despite significant progress in recent years toward a more balanced application of the First Amendment in public schools – including more study about religion in the curriculum and greater protection for student religious expression — many religious Americans remain convinced that public education is hostile to their faith. Unfortunately, some misguided school officials appear determined to prove them right.

Charles C. Haynes is senior scholar at the First Amendment Center, 555 Pennsylvania Ave., N.W., Washington, D.C. 20001. Web: firstamendmentcenter.org. E-mail: chaynes@freedomforum.org.