The work by Spanish artist Antoni Miralda titled "Poetical Gut" is on display at Copia, a food, wine and arts museum. The 35 squatting figurines are exhibited on glass shelves in a case. Bed pans and chamber pots are on other shelves.
"When it's degrading, everybody knows it except the spin doctors who run the museums," William Donohue, president of the Catholic League for Religious and Civil Rights, said Sunday.
Donohue has not visited the exhibit but said his attorney has seen the figurines. His 350,000-member, New York-based group has written to the museum's board of trustees complaining they find the show offensive.
Museum spokeswoman Holly Krassner said the center has received only three complaints and a handful of negative e-mail messages since the exhibit opened in November.
Krassner said the "caganers" or figurines are part of Spain's Catalonian peasant tradition dating back to the 18th century. One is typically placed in a Nativity scene to bring families good luck and good health.
The museum, mainly funded by private donations, plans to keep the exhibit until April.
"People who are offended by this kind of art take things too literally," said Kathy Kearns, of Crockett, California, who visited Copia on Saturday. "I think it's perfect for a food exhibit because it shows the process."
Some viewing the display laughed, saying they were not offended.
"It's a bit of a reach. And I'm Catholic," said Barbara Gaspers, of Seattle.
It's not the first time a religious group has been upset by an artist's depiction of its icons.
A collage of the Virgin of Guadalupe clad in a flowery two-piece swimsuit was displayed at a state-run folk museum in Santa Fe, New Mexico, last year.
In 1999, New York's city-funded Brooklyn Museum of Art invoked the ire of then-Mayor Rudolph Giuliani when the invited Sensation show featured an elephant dung-embellished Virgin Mary. The mayor froze the museum's annual $7.2 million city subsidy -- about a third of its annual budget -- then sued in state court to evict the museum.
The museum filed a countersuit in federal court, where a judge ruled that the city had violated the First Amendment and restored the funding.
Last year, Giuliani appointed a 20-member "decency commission" to judge the morality of public art after the Brooklyn Museum featured a 5-foot-tall (1.5-meter-tall) photograph of a nude black woman portraying Jesus surrounded by disciples, titled "Yo Mama's Last Supper."
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