The choice had been popular with students and school officials for a decade. The old high school gym was hot, cramped and uncomfortable, they said. The Elmbrook Church was modern, spacious and air-conditioned. But as the court noted, “towering over the graduation proceedings … was a 15- to 20-foot-tall Latin cross, the preeminent symbol of Christianity.”

The appeals court said that goes too far, turning a public school ceremony into an “endorsement” of a particular religion.

Nine students and parents, all unnamed, sued the school district, saying they felt uncomfortable and offended by having graduation in an evangelical church. Christians should “stop and think about how it would feel if their high school graduation ceremonies were held in a Jewish temple or Muslim mosque, where diplomas were handed out beneath a looming Star of David or Islamic crescent,” said Ayesha Khan, legal director for Americans United for Separation of Church and State, which represented the winning plaintiffs.

Since March 29, the justices have considered the Elmbrook case at their weekly conferences but taken no action, raising the chances the appeal will be turned down.

If so, the 7th Circuit’s decision will stand as a warning to school districts that they could be forced to pay damages and heavy court costs if they hold events in church buildings.