Allowing public school teachers to teach at parochial schools does not violate the Establishment Clause as long as the material that is taught is secular and neutral in nature and no "excessive entanglement" between government and religion is apparent. Decided June 23, 1997 (argued April 15, 1997). Opinion of the Court: Sandra Day O'Connor → go there Dissenting: Souter, Ginsburg. Topic: Freedom of religion. Agostini v. Felton, 521 U.S. 203 (1997), is a landmark decision of the Supreme Court of the United States. In this case, the Court overruled its decision in Aguilar v. Felton (1985), now finding that it was not a violation of the Establishment Clause of the First Amendment for a state-sponsored education initiative to allow public school teachers to instruct at religious schools, so long as the material was secular and neutral in nature and no "excessive entanglement" between government and religion was apparent. This case is noteworthy in a broader sense as a sign of evolving judicial standards surrounding the First Amendment, and the changes that have occurred in modern Establishment Clause jurisprudence. Wiki link