And at least in court, he won. In February 2012, after the Supreme Court declined to intervene in Bronx Household of Faith v. Board of Education, the doors officially closed for several years on religious groups seeking accommodations that the NY public schools gave other groups. However, various court actions dragged out the issue until it later got mooted:

On the last Sunday before a city policy went into effect barring religious services in public schools, leaders of congregations around the city expressed a range of responses, with some taking a pragmatic attitude and others vowing to not give up without a fight. …

After years of litigation, a federal court recently upheld the city’s decision to not allow services in public schools, and the city set Sunday as the deadline for dozens of congregations that had been meeting in schools to move out.

“It isn’t right what’s happened,” Mr. Schefter said of the court’s decision, “but we’re fighting the good fight, and God’s opening doors for us.”

The next day, Bloomberg called a news conference to offer an unapologetic defense of his policy. The Constitution, Bloomberg claimed, was clear on the separation of church and state:

Mr. Bloomberg, asked about the issue at a news conference, was emphatic in his defense of the city’s position.

“You know, the Constitution seems to me to be pretty clear,” he said, when asked if he would be amenable to a compromise.

“I’ve always thought that one of the great things about America is that we keep a separation” between church and state, he said, “and the more clear that separation is, the more those people who want to be able to practice their religion will have the opportunity to do so.”

“For those that want to get rid of those separations,” he added, “let me just point out: Someday the religion that’s practiced there may not be your religion, and you might in that sense look back and say let’s keep the two separate. It’s one of the basics of this country, and I will certainly support it.”

This is, to put it mildly, an ignorant position. There is nothing in the Constitution that requires public schools to refuse the same service to religious groups that they offer to non-religious groups. Bloomberg’s argument further sets up a straw man that somehow people objected to certain religious groups renting out facilities, which has no basis in fact in this case. And of course, the Constitution has no mention at all of a “separation” between church and state. It only has a prohibition against the establishment of a state religion, which facility rentals on an ecumenical basis don’t even come close to threatening.

The court rulings on this issue are interesting in terms of the bench’s tendency to conduct activism. The question presented to them was that the Bloomberg and school board policy were unconstitutional, but could they just have been stupid? In 2014, when the 2nd Circuit voted 2-1 to vacate an injunction ordered later against enforcement of the regulation, the court specifically avoided a ruling on whether the regulation was necessary in the first place. Nor did they rule on the wisdom of such a policy:

As in Bronx Household IV, we do not reach the question whether the Board would violate the Establishment Clause by allowing the subsidized use of the school facilities for religious worship services because we believe it is unnecessary to do so.

Score one for judicial modesty? Perhaps not. Judge John Walker, in his dissent, argued that the court should have made that clear to expose the discriminatory conduct of the school board, and of Bloomberg in pushing the case:

The majority states that the “Free Exercise Clause . . . has never been understood to require government to finance a subject’s exercise of religion.”   Maj. Op. at 9.  Allowing an entity to use public school space open to all others on equal terms is hardly the financing of that entity.  However, shutting the door to religious worship services in such a setting when every other activity is permitted strikes at the Clause’s core.    “Indeed, it was historical instances of religious persecution and intolerance that gave concern to those who drafted the Free Exercise Clause.”  Church of the Lukumi Babalu Aye, Inc. v. City of Hialeah, 508 U.S. 520, 532 (1993) (internal quotation marks omitted).    To this end, “[a]t a minimum, the protections of the Free Exercise Clause pertain if the law at issue discriminates against some or all religious beliefs or regulates or prohibits conduct because it is undertaken for religious reasons.”    Id.    In my view, the Board of Education’s policy that disallows “religious worship services” after hours in public schools—limited public fora that are otherwise open to all— violates the Free Exercise Clause because it plainly discriminates against religious belief and cannot be justified by a compelling government interest.   I would affirm the district court’s permanent injunction.

That was the point that the majority danced around for a long period of time. If public schools offer their facilities to rent, then they should not be allowed to discriminate against religious organizations, even if they discriminate against all religious organizations to an equal extent.

In March 2015, the Supreme Court again declined to take up the issue, leaving the 2nd Circuit decision intact. However, by that time New York City had a new mayor and a new policy. Despite his reputation for hard-progressive extremism, Bill de Blasio reversed Bloomberg’s policy and ordered the school board to allow religious groups to rent facilities on the same basis as non-religious groups. Politico covered it at the time:

Mayor Bill de Blasio’s office said religious groups will continue to have access to public school facilities, despite a decision by the nation’s highest court Monday to leave in place a lower court’s decision in favor of the city Board of Education policy that bars such activity.

In a statement, de Blasio spokesman Wiley Norvell said the administration “remains committed to ensuring that religious organizations are able to use space in City schools on the same terms provided to other groups.”

“Now that litigation has concluded, the City will develop ‘rules of the road’ that respect the rights of both religious groups and non-participants,” Norvell said.

Almost five years have gone by since then. Yet the Constitution still stands and no one’s getting indoctrinated into a state religion! Whodathunkit? The fact that this continued and created no problems for either secular or religious groups is a testament to the common sense and tolerance of Americans, and the shrieking silliness of the people who attempted to stop it in the first place.

Of all the oppo research getting dropped on Bloomberg this month, though, this probably has the least chance of getting a mention in Wednesday’s Nevada debate. To put it mildly, Democratic presidential contenders aren’t inclined toward Free Exercise defenses these days, even if de Blasio was five years ago. Most of them, if not all of them, would probably have done exactly what Bloomberg did.