Every September, on the eve of Yom Kippur, certain streets in Crown Heights, Borough Park, and South Williamsburg become a bloody and feathered stage for two opposing groups. Animal rights activists corralled behind police barricades scream "Murderers!" while ultra-Orthodox Jewish families perform Kaporos—a ritual that involves swinging live chickens by the wing, reciting sin-absolving prayers, and killing the chickens with deft slices to the neck.

And this year, well in advance of Yom Kippur 2015, Kaporos opponents are taking their fight to the courts. The Alliance to End Chickens as Kaporos—a group that has hosted multiple pro-chicken rallies around Brooklyn in recent years—has filed suit against the city, the Health Department, and prominent rabbis, in the hopes of banning the ritual altogether. In an affidavit, quoted at length in the Daily News, the Alliance's lawyers argue that the ritual is not only a health risk, but one that has ballooned in recent years:

"Ten years ago, Kaporos only occurred in several small alleys and a handful of synagogue parking lots. However, every year it has increased in size and scope. Today, Kaporos has become an overwhelming event that has spiraled out of control... [into] a carnival like atmosphere of bloody violence."

Because large Orthodox families tend to purchase their Kaporos chickens from synagogues, activists argue that "this event is now motivated by money and profits, and not by religious redemption." Kaporos organizers have long maintained that the dead chickens are donated to food banks and poor families, while activists claim many of the dead chickens have simply been tossed in plastic bags and sent to landfills.

The lawsuit describes, in graphic detail, streets clogged with "dead chickens, half dead chickens, chicken blood, chicken feathers, chicken urine, chicken feces, other toxins and garbage," piling on affidavits from neighbors who say the headless chickens make them nauseous.

For his own part, "I don't know what in God's name they're talking about," Borough Park Assemblyman Dov Hikind told the Post. "They make it sound like there's blood running in the streets. It's just not true."

Here's footage from last year's Kaporos, for those who have yet to take sides: