Lemon v. Kurtzman was a landmark U.S. Supreme Court case in 1971 in which the court ruled 8 to 1 that Pennsylvania’s Nonpublic Elementary and Secondary Education Act of 1968 was unconstitutional, violating the Establishment Clause of the First Amendment. The law allowed public schools to reimburse mostly Catholic private schools for the salaries of teachers who used public school textbooks and instructional materials. The high court ruled that public laws must have a secular purpose, not simply a religious purpose; must not advance nor inhibit religion; must not result in “excessive government entanglement” with religion.
The First Amendment prohibited the establishment of any religion as official in any state. Before the development of the Constitution, certain states or colonies were considered Protestant and others, such as Massachusetts and Maryland, were considered Protestant.