When not furrowing their collective brows about creches and displays of the Ten Commandments here and there, courts often are pondering tangential contacts between the government and religious schools. Courts have held that public money can constitutionally fund the transportation of parochial school pupils to classes — but not on field trips. It can fund nurses at parochial schools — but not guidance counselors. It can fund books — but not maps. Daniel Patrick Moynihan wondered: What about atlases, which are books of maps? On Wednesday, the Supreme Court will consider the constitutional significance of this incontrovertible truth: “A scraped knee is a scraped knee whether it happens at a Montessori day care or a Lutheran day care.”

That assertion is in an agreeably brief amicus brief written by Michael McConnell, a Stanford University law professor specializing in church-state relations. He requires just 13 pages to make mincemeat of Missouri’s contention that a bit of 19th-century bigotry lodged in its constitution requires it to deny shredded tires to Trinity Lutheran Church in Columbia, which runs a preschool.

Missouri’s Department of Natural Resources, which has a capacious conception of natural resources, runs the Scrap Tire Program. It enables playgrounds to replace gravel and dirt with a rubber protective surface that is kinder to the knees of the devout and heathens alike.

The department refused the church’s request for a $20,000 grant, citing this from the state constitution: “No money shall ever be taken from the public treasury, directly or indirectly, in aid of any church, sect or denomination of religion.” Trinity Lutheran says the state is abridging its First Amendment right to the “free exercise” of religion and denying the 14th Amendment guarantee of “equal protection of the laws.”

Both sides agree that the U.S. Constitution poses no impediment to Missouri giving a grant to Trinity Lutheran. The question for the Supreme Court is whether Missouri can demand an even stricter separation of church and state. Can it exclude an otherwise eligible entity from a generally available public benefit — a benefit serving a completely separate purpose (see above: knees) — simply because the entity is religious?

Missouri’s constitutional language is a Blaine Amendment, named for the Republican Speaker of the House and 1884 presidential nominee James G. Blaine. Protestants resented Catholic immigrants founding parochial schools that taught Catholicism as forthrightly as public schools taught Protestantism with prayers, hymn singing and readings from the King James version of the Bible. Each public school was, in Horace Mann’s approving words, a “nursery of piety” — Protestant piety.

Hoping that anti-Catholicism would propel him into the presidency, in 1875 Blaine unsuccessfully proposed amending the U.S. Constitution to stipulate that no public money could go to schools “under the control of any religious sect.” But 37 states put versions of his amendment into their constitutions, and Congress required its inclusion in the constitutions of states entering the union.

Even if, as Missouri implausibly insists, its constitution’s language, which was enacted in — wait for it — 1875, was unrelated to anti-Catholic animus, the language is nevertheless incompatible with the Supreme Court’s establishment clause jurisprudence. Splitting and re-splitting judicial hairs over the years, the Supreme Court has produced a three-part test: A statute pertaining to contact between government and religion does not constitute establishment of religion if the statute has “a secular legislative purpose” (again: knees), it neither advances nor inhibits religion, and it does not involve “excessive government entanglement with religion.”

Practices during the Founders’ era demonstrate, McConnell argues, that “including religious groups in neutral public benefit programs was not viewed as an establishment.” And: “Shredded tires have no religious, ideological, or even instructional content . . . a rubberized playground is existentially incapable of advancing religion.”

Missouri cites, in defense of its practice, an utterly inapposite case in which the Supreme Court upheld a state’s refusal to fund students seeking degrees in devotional theology, even though it funded degrees in secular subjects. This involved entirely different issues than Missouri denying an organization access to a public safety benefit simply because the organization is religious. Spreading shredded tires beneath a jungle gym hardly (in the Supreme Court’s language) “intentionally or inadvertently inculcates particular religious tenets.” And Missouri’s denial of this benefit is, McConnell writes, “the clearest possible example of an unconstitutional penalty on the exercise of a constitutional right,” the free exercise of religion.

“The religious status of the Trinity Lutheran day care bears not the slightest relevance to the purpose of the state’s program.” Which pertains to knees.

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