Cases arising under the United States Constitution's religion clauses fall into four general categories. In the first category are establishment clause controversies involving the provision of government services or aid. For example, when the government seeks to provide educational assistance to all private schools, financial aid to parochial schools is usually challenged on establishment clause grounds.
Gary C. Leedes,
Court-Ordered Exemptions to Secure Religious Liberty,
U. Rich. L. Rev.
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