Mueller v. Allen (1983)

The Supreme Court examined whether a Minnesota state law violated the Establishment Clause of the First Amendment. The law allowed taxpayers to deduct from their state income tax expenses incurred in providing tuition, textbooks, and transportation for their children’s elementary or secondary school education—including for private secular and parochial schools.

In a 5-4 decision, the Court upheld Minnesota’s tax-credit law as constitutional because—applying the three-pronged test from Lemon v. Kurtzman (1971)—the tax credits did not have the effect of advancing religion (primarily secular purpose), were available to all parents and applied to sectarian and nonsectarian tuition (principal effect neither aids nor inhibits religion), and did not excessively entangle government and religion.