The Supreme Court, in an increasingly familiar development, handed a victory to a Christian conservative organization on Monday. The Court’s decision in Shurtleff v. Boston establishes that this organization, Camp Constitution, should have been allowed to fly a Christian-identified flag from a flagpole outside Boston’s city hall.

But Shurtleff is unlike several other high-profile victories for religious conservatives that the Court has handed down in recent years because the justices did not need to remake existing law in order to reach this result. The decision was unanimous (although the justices split somewhat regarding why the plaintiffs in this case should prevail), with liberal Justice Stephen Breyer writing the majority opinion.

The case involves three flagpoles standing outside of Boston’s city hall. The first flagpole displays the US flag, with a smaller flag honoring prisoners of war and missing service members below it. The second pole features the Massachusetts state flag. And the third typically — but not always — displays the city’s own flag.

This third flagpole, and the city’s practice of sometimes allowing outside groups to display a flag of their choice from it, is the centerpiece of Shurtleff. Since at least 2005, the city has permitted outside groups to hold flag-raising ceremonies on the plaza during which they can raise a flag of their choosing on the third flagpole.

At various times, the third flagpole has displayed the flags of many nations, including Brazil, China, Ethiopia, Italy, Mexico, and Turkey. It has displayed the rainbow LGBTQ pride flag, a flag commemorating the Battle of Bunker Hill, and a flag honoring Malcolm X.

But when Harold Shurtleff, head of an organization called Camp Constitution, asked to fly a flag associated with the Christian faith, the city refused — claiming that displaying such a flag could be interpreted as “an endorsement by the city of a particular religion,” in violation of “separation of church and state or the [C]onstitution.”

Justice Breyer’s majority opinion concludes that the city erred. Relying on a bevy of cases establishing that the government typically cannot discriminate against a particular viewpoint, Breyer notes that “Boston concedes that it denied Shurtleff’s request solely because the Christian flag he asked to raise ‘promot[ed] a specific religion.’” Under the facts of this case, that’s a form of viewpoint discrimination and it’s not allowed.

While it’s notable that Justices Neil Gorsuch and Brett Kavanaugh both wrote separate opinions indicating that they are eager to let government get cozy with religion, and they have two opportunities to do so this term, this case is a straightforward decision that follows current law — in short, nothing remarkable.

The immediate stakes in Shurtleff, moreover, are fairly small. As Breyer notes in his opinion, other cities have lawful policies that permit only certain flags to be displayed on government-owned flagpoles. And “nothing prevents Boston from changing its policies going forward.”

But the policy that was in effect in 2017, when Shurtleff asked to display a Christian flag from Boston’s flagpole, is not allowed.

The case turns upon who was “speaking” when flags were raised on the third flagpole

The general rule in free speech cases is that the government may not discriminate against any particular viewpoint. Boston could not, for example, have a rule that Democrats are allowed to gather in the city hall plaza but not Republicans. Or that people who support restrictive immigration policies may do so, but not people who oppose them.

But there’s an exception to this general rule when the government speaks in its own voice. That is, the government is allowed to express its own opinion on a subject without also providing a forum for dissenting voices. If a public school principal tells her students to “say no to drugs,” she’s not required to give equal time to the grungy guy in the junior class who sells weed out of his 1997 Subaru Legacy.

The primary question in Shurtleff is whether, when Boston’s city government permitted a wide range of private groups — but not Camp Constitution — to display a flag of their choice outside of city hall, these flags represented the city’s speech or the private groups’ speech. Again, if the flags were a form of government speech, then Boston is allowed to exclude viewpoints it does not share.

But the Court concluded that the city did not use the third flagpole to express its own views, and that it effectively created “a forum for the expression of private speakers’ views.” As Breyer notes, Boston does not appear to have made any effort whatsoever to control which flags are displayed from this flagpole until it denied Shurtleff’s request to fly a Christian flag.

“Between 2005 and 2017,” Breyer notes, “Boston approved about 50 unique flags, raised at 284 ceremonies. Boston has no record of refusing a request before the events that gave rise to this case.” The city official who approved flag-raising ceremonies testified that, under his ordinary practice, he “‘never requested to review a flag or requested changes to a flag in connection with approval’; nor did he even see flags before the events.”

Thus, on these facts, Boston could not properly claim that it was expressing its own views when it allowed a flag to be raised on one of its flagpoles.

That said, Breyer’s opinion explicitly permits Boston to change its policy to allow it to exclude Christian (and other) flags. Breyer contrasts Boston’s policy with one in San Jose, California, which “provides in writing that its ‘flagpoles are not intended to serve as a forum for free expression by the public,’ and lists approved flags that may be flown ‘as an expression of the City’s official sentiments.’”

If Boston wants to adopt a San Jose-style policy in the future, where it maintains much tighter control over which flags are displayed on its flagpole, it may do so.

Several justices want to take a sledgehammer to the wall separating church and state

As mentioned above, Boston justified its decision to deny Shurtleff’s request because it believed that doing so would violate the constitutional prohibition against government endorsement of religion. Under existing precedents, that was an error.

Among other things, as a practical matter the government can’t endorse something if it’s not speaking in its own voice; if the Christian flag is Camp Constitution’s speech and not Boston’s speech, then the government isn’t endorsing any viewpoint when this flag is displayed. And, for the reasons laid out in Breyer’s opinion, Boston’s city government was not speaking in its own voice when it permitted private groups to use its flagpole.

Nevertheless, several justices appear eager to tear down the rule that the government may not endorse a particular religious viewpoint altogether.

This ban on government endorsement of religion was embraced by the Supreme Court in Lemon v. Kurtzman (1971), which held, among other things, that the “principal or primary effect” of a government policy can’t be one that “advances nor inhibits religion.”

But Gorsuch, in an opinion joined by Justice Clarence Thomas, claims that courts should no longer follow Lemon — claiming that Lemon’s rule has “produced only chaos.” Kavanaugh, meanwhile, also published a short concurring opinion warning that “this dispute arose only because of a government official’s mistaken understanding of the Establishment Clause” — the clause that requires a degree of separation of church and state.

These asides by Gorsuch and Kavanaugh aren’t particularly surprising. At an oral argument last week, both justices appeared eager to overrule Lemon. And, in an argument last December, Kavanaugh even suggested that the government may, in certain circumstances, be required to fund religious education — because, he suggested, “discriminating against all religions” is not allowed.

So, while Shurtleff is a minor case that largely just applies existing law to Boston’s flagpole, the concurring opinions in Shurtleff suggest that a storm is coming. The Court is likely to remake much of its jurisprudence involving the Establishment Clause, even if it is likely to wait a few more weeks before it does so.