Although participating private schools must comply with performance, reporting, auditing, health, safety, and antidiscrimination rules, Steinmetz concluded that such oversight does not amount to excessive entanglement. As Steinmetz observed, the MPCP does not call for government involvement in private schools' governance, curriculum, or daily activities. The most challenging part of the Lemon test in this situation concerned whether the voucher program advances religion as its primary effect. To address this question, Steinmetz reviewed 50 years of U.S. Supreme Court precedent, beginning with Everson v. Board of Education in 1947 and culminating in Agostini v. Felton in 1997. The big turning point that paved the way for the Wisconsin Supreme Court's decision in this case came in 1983 in the U.S. Supreme Court's decision in Mueller v. Allen, in which it upheld a Minnesota statute that allowed taxpayers to deduct certain educational expenses in calculating their state income tax.
Students are eligible if they live in Milwaukee and meet certain income standards.
Students who receive aid are selected randomly from all applicants. Participating schools can be either religious or non-religious, and they must accept MPCP students randomly, although they may give a preference to siblings already attending the school. The opt-out provision protects students from participating in religious activities against the wishes of their parents. Second, although religious schools receive benefits, they receive them through the private choices of individual parents rather than through the decisions of government agencies. Justice Steinmetz rejected the plaintiffs' claim that the MPCP violates the Equal Protection Clause's prohibition against racial discrimination.