Mueller v. Allen, 463 U.S. 388 (1983), was a United States Supreme Court case examining the constitutionality of a state tax deduction granted to taxpaying parents for school-related expenses, including expenses incurred from private secular and religious schools. The plaintiffs claimed that a Minnesota statute, allowing tax deductions for both public and private school expenses, had the effect of subsidizing religious instruction since parents who paid tuition to religious schools received a larger deduction than parents of public school students, who incurred no tuition expenses.