At issue in Illinois ex rel. McCollum v. Board of Education (1948) was the constitutionality of released time for religious instruction in public schools. McCollum dealt with the power of a state to utilize its tax-supported public school system for religious instruction. The Court found that this usage violated the Establishment Clause not only because the school property was used for religious classes but also because school officials and the clergy teachers had a close working relationship. The role of religion in public schools is a subject of continued debate with advocates and opponents. McCollum is important because it helped to set guidelines for permissible and acceptable parameters for the role of religion in public schools.