In 1997, Isbell purchased a building in San Diego with the intent to open an adult entertainment establishment there. Because this building was located within 1,000 feet of a residential area, however, a San Diego zoning ordinance precluded him from operating there. Isbell applied for a variance but was unsuccessful. He then filed suit, arguing that the city’s ordinance violates the First Amendment, and that its standards for variances violate the equal protection clause. Can the city restrict the operation of this business? What must the city be able to establish? [Isbell v. City of San Diego, 258 F.3d 1108 (9th Cir.)]