The Volokh Conspiracy
Mostly law professors | Sometimes contrarian | Often libertarian | Always independent
The Governor of Mississippi hasn't required shutdown of in-person church services (though on its face his shelter-in-place order lack such an exception). The mayor of Greenville, however, has issued an Executive Order "that orders all church buildings closed for in person and drive in church services." Greenville has reportedly been fining people for attending a drive-in service, including where "Everyone was in their cars with the windows up listening to pastor Arthur Scott preached on the radio."
That, I think, is inconsistent with the Mississippi Religious Freedom Restoration Act, which provides that "Government shall not substantially burden a person's exercise of religion even if the burden results from a rule of general applicability," unless the government "demonstrates that application of … [i]s the least restrictive means of furthering [a] compelling governmental interest." A shutdown of ordinary in-person church services may well be the least restrictive means of furthering a compelling government interest in preventing the spread of coronavirus. But a shutdown that includes drive-in services is not the "least restrictive means": Limiting the shutdown to in-person services would be a less restrictive means that would still adequately protect public health. (About 30 states have RFRA-like laws, or similar legal rules developed by state courts under the state constitutions' religious freedom provisions.)
I take it that the strongest counterargument would be, to quote the Mississippi Governor who was discouraging but not banning such services, "It's just hard to overcome our natural tendency to get out and say hello." But that doesn't seem obviously so to me—when people show up to a drive-in event precisely because it's a drive-in event, it seems to me quite natural for the people to stay in their cars. And while one can imagine the government showing the contrary, the burden would be on the government to "demonstrate" that.
Even in the absence of the Mississippi RFRA, I think the restriction would violate the the Assembly Clause and the right to associate. (The First Amendment speaks of "the right of the people peaceably to assemble, and to petition the Government for a redress of grievances," but the Court has read assembly/association rights as extending to action related to "political, economic, religious or cultural matters" and not just assembly and association for purposes of petitioning the Government.)
A ban on all gatherings of more than 10 people, including in their cars, may be content-neutral, but I doubt that it leaves open ample alternative channels for peaceable assembly. And even if the ban just had to be substantially related to an important government interest—the test applicable to content-neutral restrictions that do leave open ample alternative channels—I think it would still fail when applied to people gathering in their cars and being communicated to via radio (or cell phones or some such).