United States Supreme Court Justice Elena Kagan, the junior justice, dove right into her first dissent Monday in a case involving the First Amendment's Establishment Clause. She was blunt, she was pointed, and she brought three of her senior colleagues along with her in full. It's probably a little too early to make any predictions but Justice Antonin Scalia, the Court's legendary dissenter, may finally have some company in that rarefied air.

The case was Arizona Christian School Tuition Organization v. Winn and it generated the sort of 5-4 ideological split we've seen so often from the Court in recent years. The Court's conservative majority, led by Justice Anthony Kennedy, ruled that taxpayers in Arizona had no legal standing to challenge a state law that gives tax credits for contributions to "school tuition organizations" which then provide scholarships to students attending private schools and (here is where the First Amendment comes in) religious schools as well.

Justice Kennedy and his colleagues concluded that because the state created the incentive by offering a "tax credit," as opposed to making a "government expenditure," there was no standing for taxpayers to complain about the hundreds of millions of dollars diverted each year from the general budget for such purposes. He made the distinction because he needed to get around longstanding Court precedent that allows such lawsuits to proceed in case involving "expenditures." Justice Kennedy wrote:

It is easy to see that tax credits and governmental expenditures can have similar economic consequences, at least for beneficiaries whose tax liability is sufficiently large to take full advantage of the credit. Yet tax credits and governmental expenditures do not both implicate individual taxpayers in sectarian activities. A dissenter whose tax dollars are "extracted and spent" knows that he has in some small measure been made to contribute to an establishment in violation of conscience. In that instance the taxpayer's direct and particular connection with the establishment does not depend oneconomic speculation or political conjecture. The connection would exist even if the conscientious dissenter's tax liability were unaffected or reduced. When the government declines to impose a tax, by contrast, there is no such connection between dissenting taxpayer and alleged establishment. Any financial injury remains speculative. And awarding some citizens a tax credit allows other citizens to retain control over their own funds in accordance with their own conscience.

That quote is one of the most important quotes a Supreme Court justice has offered all term because its rationale opens the door to state legislation across the nation that would codify tax incentives for religious schools. In essence, it broadens by an order of magnitude an exception to the First Amendment's Establishment Clause, which is designed to separate church and state. It was a point, and a demarcation line, that Justice Elena Kagan recognized and attacked. In dissent, she wrote:

This novel distinction in standing law between appropriations and tax expenditures has as little basis in principle as it has in our precedent. Cash grants and targeted tax breaks are means of accomplishing the same government objective--to provide financial support to select individuals or organizations. Taxpayers who oppose state aid of religion have equal reason to protest whether that aid flows from the one form of subsidy or the other. Either way, the government has financed the religious activity. And so either way, taxpayers should be able to challenge the subsidy. Still worse, the Court's arbitrary distinction threatens to eliminate all occasions for a taxpayer to contest the government's monetary support of religion. Precisely because appropriations and tax breaks can achieve identical objectives, the government can easily substitute one for the other. Today's opinion thus enables the government to end-run Flast's guarantee of access to the Judiciary. From now on, the government need follow just one simple rule--subsidize through the tax system--to preclude taxpayer challenges to state funding of religion.

The "Flast" of which Justice Kagan wrote is Flast v. Cohen, a 1968 Supreme Court ruling which allowed the sorts of taxpayer lawsuits sought here. That case didn't determine an outcome, mind you, it just merely allowed plaintiffs like the ones in this case to be able to have the merits of their claims heard by the Court. That will not happen in this case. Again, Justice Kagan:

[Justice Kennedy's] distinction finds no support in case law, and just as little in reason. In the decades since Flast, no court--not one--has differentiated between appropriations and tax expenditures in deciding whether litigants have standing. Over and over again, courts (including this one) have faced Establishment Clause challenges to tax credits, deductions, and exemptions; over and over again, these courts have reached the merits of these claims. And that is for a simple reason: Taxpayers experience the same injury for standing purposes whether government subsidization of religion takes the form of a cash grant or a tax measure. The only rationale the majority offers for its new-found distinction--that grants, but not tax expenditures, somehow come from a complaining taxpayer's own wallet--cannot bear the weight the Court places on it. If Flast is still good law--and the majority today says nothing to the contrary--then the Plaintiffs should be able to pursue their claim on the merits.

She was even willing to spend some time offering a "hypothetical" to make her point -- just like they taught her at Harvard Law School. Justice Kagan wrote:

Our taxpayer standing cases have declined to distinguish between appropriations and tax expenditures for a simple reason: Here, as in many contexts, the distinction is one in search of a difference. To begin to see why, consider an example far afield from Flast and, indeed, from religion. Imagine that the Federal Government decides it should pay hundreds of billions of dollars to insolvent banks in the midst of a financial crisis. Suppose, too, that many millions of taxpayers oppose this bailout on the ground (whether right or wrong is immaterial) that it uses their hard-earned money to reward irresponsible business behavior. In the face of this hostility, some Members of Congress make the following proposal: Rather than give the money to banks via appropriations, the Government will allow banks to subtract the exact same amount from the tax bill they would otherwise have to pay to the U. S. Treasury. Would this proposal calm the furor? Or would most taxpayers respond by saying that a subsidy is a subsidy (or a bailout is a bailout), whether accomplished by the one means or by the other? Surely the latter; indeed, we would think the less of our countrymen if they failed to see through this cynical proposal.

Contrast Justice Kagan's dissent with those of her newly-minted colleagues. Justice Sonia Sotomayor, who came to the Court in 2009, authored her first major dissent in a case involving the narrowing of the Miranda warning. It was solid but had little of the rhetorical flair or bite that Justice Kagan offered up Monday. Justice Samuel Alito, who came to the Court in 2006, also authored his first major dissent in a case involving the rights of criminal defendants. But he did not dissent alone in that case. And Chief Justice John Roberts, who came to the Court in 2005, authored his first dissent in a case involving search warrants. The first two lines of his work were good. The Chief Justice wrote:

The Court creates constitutional law by surmising what is typical when a social guest encounters an entirely atypical situation. The rule the majority fashions does not implement the high office of the Fourth Amendment to protect privacy, but instead provides protection on a random and happenstance basis, protecting, for example, a co-occupant who happens to be at the front door when the other occupant consents to a search, but not one napping or watching television in the next room.

So good, in fact, that the ol' dissenter himself, Justice Scalia, joined in. I guess that's the next milestone to wait for from the High Court -- the day when Justices Scalia and Kagan join together in dissent. What a doozy that might be.