The First Amendment's Establishment Clause prohibits the government from making any law “respecting an establishment of religion.” This clause not only forbids the government from establishing an official religion, but also prohibits government actions that unduly favor one religion over another. It also prohibits the government from unduly preferring religion over non-religion, or non-religion over religion.
Although some government action implicating religion is permissible, and indeed unavoidable, it is not clear just how much the Establishment Clause tolerates. In the past, the Supreme Court has permitted religious invocations to open legislative session, government funding of bussing and textbooks for private religious schools, and efforts by school districts to arrange schedules to accommodate students’ extra-curricular religious education programs. The Court has ruled against some overtly religious displays at courthouses, state funding supplementing teacher salaries at religious schools, and some overly religious holiday decorations on public land.
One point of contention regarding the Establishment Clause is how to frame government actions that implicate religion. Framing questions often arise in the context of permanent religious monuments on public land. Although it is reasonably clear that cities cannot install new religious monuments, there is fierce debate over whether existing monuments should be removed. When the Supreme Court recently considered this issue in Van Orden v. Perry, 545 U.S. 677 (2005), and McCreary County v. ACLU, 545 U.S. 844 (2005), it did not articulate a clear general standard for deciding these types of cases. The Court will revisit this issue in its 2009-10 term when it hears Salazar v. Buono (08-472), a case considering the constitutionality of a large white Christian cross on federal land in the Mojave Desert.