Most weekdays, some 2,700 students crowd the sidewalks and hallways of Capistrano Valley High School, which is a quick drive from Orange County, California’s finest beaches. Capo, as the school is informally known, boasts a champion surf team as well as a prestigious academic reputation, among other distinctions.

The world’s most powerful megachurch, Saddleback, is about eight miles south of Capo; nearby are the skyline-dominating Crystal Cathedral and the nation’s largest Christian broadcast network. Non-Christian faiths, too, have set up shop in the OC, home to growing numbers of Muslim, Hindu, Buddhist and Zoroastrian worshipers. In fact, for all the associations of Orange County with implants and Botox and for all the TV shows that depict a shamelessly decadent lifestyle, such as “The Real Housewives of Orange County,” this is foremost a highly religious place.

All of which has come to play out in the classroom of history teacher James Corbett, the defendant in a federal lawsuit that, depending on its outcome in the U.S. Court of Appeals for the Ninth Circuit, could threaten traditional notions of academic freedom.