The Constitutional provision that the state policy must abide by is the Establishment Clause--"Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof . . ." This certainly doesn't require that a state deny religious nonprofits to receive grants for resurfacing their daycare playgrounds. The question the Court has certified already acknowledges that there is no Establishment Clause issue, which is a direct consequence of the case law.
I'll take your word for this, but find it interesting that Cornell University Law School has titled its Supreme Court Bulletin regarding the case as
Trinity Lutheran Church of Columbia, Inc. v. Pauley [with the following links]
First Amendment
Free Exercise Clause
Establishment clause
Equal protection
Separation of church and state
And headlines the issue as:
"Issues
Does Missouri violate the First Amendment by denying churches governmental aid awarded with neutral criteria and a secular purpose?"
source
The US Court of Appeals has taken the case because of Sara Parker Pauley's decision, which was based on Missouri's constitutional article written in 1875:
Public aid for religious purposes--preferences and discriminations on religious grounds.
Section 7. That no money shall ever be taken from the public treasury, directly or indirectly, in aid of any church, sect or denomination of religion, or in aid of any priest, preacher, minister or teacher thereof, as such; and that no preference shall be given to nor any discrimination made against any church, sect or creed of religion, or any form of religious faith or worship.
Source: Const. of 1875, Art. II, § 7.
What I also found interesting was the DNR's paraphrased argument here, which reads in part:
Sara Parker Pauley, director of the Missouri DNR, (hereinafter, “DNR”) argues that the State’s decision not to subsidize Trinity Lutheran does not violate the Free Exercise Clause because the Clause only stops the government from prohibiting the free exercise of religion but does not require that the government provide funding to religious organizations. DNR contends that Trinity misinterprets the Free Exercise Clause and ignores its text, history, and the Court’s precedent. DNR maintains that the plain language of the text limits only government action that “prohibits” the free exercise of religion.
Furthermore, DNR notes that the government does not have an obligation to fund its citizen’s exercise of their constitutional rights; indeed, DNR notes that the Clause is written as what the government cannot do to the individual and not in terms of the entitlements that an individual may get from the government. DNR contends that Trinity’s ability to exercise its constitutional right to religion does not depend on government support and, moreover, its request for playground-resurfacing funding is secular and not a “generally available public benefit” because of the limited number of recipients. DNR analogizes Trinity’s claims to those that failed in Locke v. Davey, in which the Court held that Washington’s refusal to provide financial aid to a student pursuing a theology degree was not a Constitutional violation because of the “minimal burden” that the policy placed on the student’s right to freely exercise his religion.
source
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