Marsh v. Chambers
From Conservapedia
In Marsh v. Chambers, 463 U.S. 783 (1983), the U.S. Supreme Court upheld the constitutionality of the Nebraska State Legislature's practice of opening each of its sessions with a prayer offered by a chaplain paid out of public funds. The opinion also noted that benedictions and invocations at public school graduations are not always unconstitutional.
