(Bloomberg) -- Off-Broadway theaters and comedy clubs in New York City say they’re being unfairly singled out by a city policy that requires them to verify that their patrons are vaccinated against Covid-19 before letting them in. 

A group of small entertainment venues sued Mayor Bill de Blasio Thursday claiming the vaccine mandate -- called Key to NYC -- is discriminatory because it applies to them when they are staging theater or comedy shows but does not apply to churches or other places of worship that are using the same venues for religious services

The rule “discriminates against plaintiffs by singling out theaters and comedy clubs for more restrictive treatment based on the content of speech that theaters and comedy clubs host.”

De Blasio announced the rule in August. It requires patrons and employees to show proof that they have had at least one vaccine dose. The order applies to indoor restaurants, gyms, concert halls and theaters, including movie theaters -- but not places of worship.

During the pandemic, lawmakers have had to tiptoe around pandemic rules aimed at churches, which have argued successfully in court that the Constitution’s First Amendment prohibits any law that infringes on the free exercise of religion.

The city didn’t immediately respond to an emailed request for comment, sent after regular business hours.

In their suit, the theater and comedy club owners say that the vaccine mandate is the latest in a long series of hardships they have faced since they were shut down at the start of the pandemic.

“For small venue theaters and comedy clubs like plaintiffs, enforcing this unequal mandate is burdensome and further stigmatizes businesses that are already struggling to bounce back from being shut down for a year,” the owners say.

The case is Players Theater Management Corp. v. De Blasio, 21-cv-07779, U.S. District Court, New York Southern District (Manhattan).

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