The question in this case is whether the plaintiffs have standing to challenge a tax credit that Arizona is giving to private school donors. most of whom are contributing to religious schools. Let's ignore stare decisis for a moment. No one relies on "standing" jurisdiction in ordering their affairs, so observing precedent isn't terribly important. Suppose, instead that our "standing" jurisprudence consists of (i) the "case or controversy" language in Article III and a prudential notion that a citizen, qua citizen, has no standing to complain of governmental action. One good reason for such a rule is that someone who is actually aggrieved by the government action is a better representative of his side of the argument than a citizen who is merely, allegedly, opposed to it. I mean, how do we know that the complaining citizen is really not just shilling for the government, that he won't lie down and play dead once the case is brought? Moreover, the courts are too busy to waste time on complaints without real complainants. If no one is hurt enough to complain, why bother to address the alleged problem? (I'm sure all of this has been covered ad nauseam in the relevant authorities, but we're just a couple of guys talking here, not legal scholars, so we'll leave reading the authorities to people who get paid.)
In most constitutional matters, the challenged action does affect someone directly. Someone is held liable for exercising free speech, or denied a permit to assemble peaceably, or not allowed to bear arms, or searched unreasonably, or not Mirandized, or denied counsel, or sentenced cruelly and unusually. But is the same thing true of the Establishment clause?
Suppose that Arizona, instead of allowing a tax credit for donations, had gone right out and declared Shinto the "State religion," but only in the sense that the saguaro cactus flower is the state flower, i.e., with no legal consequence to anyone. Who could complain? Who is hurt? Suppose some guy is denied a job by a private employer on the grounds that he is not a follower of Shinto, the employer reasoning, and admitting, that he believes it's good politics and customer relations for him to hire someone of the state's "official" religion. Our victim might then have a case. But doesn't he already have one under Title VII of the Civil Rights Act? Would he ever get to the Establishment clause? Indeed, is it possible to envision a violation of the Establishment clause that prejudices an individual but does not give rise to a complaint under the "equal protection" provision of the Fourteenth Amendment or some civil rights statute or other?
So, as a practical matter, it may well be that the only violations of the Establishment clause that don't have a remedy outside the Establishment clause are those that involve spending public money to favor one metaphysical worldview over one or more others. As a result, perhaps, the chosen avenue of attack has been the taxpayer suit, wherein someone alleges that the government has misspent his money in violation of the Establishment clause, even without a demonstrable link between such action and any individual harm to the complaining taxpayer.
Enter Flast v. Cohen. In that case, the Court held that a taxpayer, qua taxpayer, can contest Congress's exercise of the taxing and spending power, and because any taxing or spending done in violation of the Establishment clause necessarily exceeds Congress's authority to act, a taxpayer can challenge an Establishment clause breach that involves spending or taxing. That may sound narrow, but recall that any other violation of the Establishment clause would almost certainly create an individual harm that would support standing by an actual aggrieved party, under some other provision of law. Thus, Flast effectively created a taxpayer's remedy for "victimless" Establishment clause violations. Or, so it seemed until Arizona Christian STO came along.
Flast seems to me to rely on the legal fiction that the plaintiff taxpayer is aggrieved because it's his money being spent. If, as Chief Justice Warren argued in Flast, standing is required to assure that the parties are "sufficiently adversarial," the tenuous interest of an individual taxpayer in an insignificant government expenditure - the plaintiff's share of which would surely be de minimis in any other context - seems weaker than that of an atheist to be protected from the consequence of that spending. It does not appear that the plaintiffs in Flast complained of harm as non-religious persons, so I don't know what would have happened if they had. Nor does it appear that the plaintiffs in Arizona Christian STO claimed anything beyond taxpayer status. Still, that seems to me the only acceptable basis for an objection to government establishmentarianism.
Arizona Christian STO points up the weakness in Flast as the only basis for standing in Establishment clause cases. Flast opens a back door, and not everyone fits through it. Non-taxpayers don't fit through it, although they may be aggrieved as members of a derogated religious minority. And now, we find, tax credits don't fit through it either. There is something ironically theological about the dispute over whether a tax credit somehow causes the state's income tax to be unconstitutional. Is forgiving a tax the same thing as spending it? The tax laws routinely allow deductions for gifts to religious organizations. Why not a credit? But I won't be lured into counting the angels on that pinhead. The question should never have arisen. Where an Establishment clause issue exists, a plaintiff should be required to show only that he is objecting on the basis of his religious views being denigrated by the state, and not on the general, problematic basis that the taxing authority has overstepped its bounds.
Flast's kludginess also raises an issue of Federalism that bothers me. I get how the Establishment clause is incorporated into the Fourteenth Amendment's guaranty of liberty, but I'm not sure whether the issue of standing to protest the misuse of state funds under a taxing power that does not arise under the U.S. Constitution is governed by Flast. Imagine a state law that, to save the state money, provides that no taxpayer suit may be brought to contest any tax or expenditure where the taxpayer plaintiff's pecuniary interest in the matter is less than $10 per year. Would such a law be unconstitutional? Would it magically become unconstitutional if applied to a case where the bad taxing or spending violated the Establishment clause? If so, would that not, er, establish that Flast is a dodge?
I believe that the plaintiffs in Arizona Christian STO v. Winn should have had standing to press their claim as members of a group disadvantaged by the law, if they could credibly make that claim. I don't know enough about the group to say. Otherwise, they should be denied standing, not because a credit is different from an expenditure - which I suspect it is, but I don't have to decide yet - but because their interest as taxpayers is de minimis and, therefore, their adversarial bona fides are not sufficient under Article III.