Idaho officials may face a sobering lawsuit over their ban on a vodka that makes a cheeky reference to polygamy, a Washington law professor says.

In a letter dated Wednesday and published on his website, George Washington University professor Jonathan Turley informs Idaho officials he will sue on behalf of the producer of Five Wives Vodka if the state doesn't reverse its decision not to allow the vodka's sale. He says the ban is unconstitutional and he gives the state 10 days to reverse its position.

Idaho State Liquor Division director Jeff Anderson said last month that the brand is offensive to Mormons who make up more than a quarter of Idaho's population and would not be sold in the state. The Mormon church at one time allowed polygamy but abandoned the practice in 1890. Anderson did not immediately respond to a request for comment Wednesday.

"Idaho is the only state to raise religious and social sensibilities as a basis to deny entry to this product," Turley wrote in his letter.

He said that a lawsuit would raise issues of free speech and other claims.

Idaho has defended its decision not to allow Five Wives Vodka, saying state liquor stores already make hundreds of vodka brands available for sale and don't have room for another brand priced at around $20 a bottle.

Five Wives Vodka is made by Ogden's Own Distillery in Utah, where the Mormon church is based, and was first sold in Utah in December 2011. It is available in Utah and Wyoming and will soon be sold in Montana, Colorado and other states.

A spokesman for Five Wives Vodka, Steve Conlin, said Wednesday that the company wasn't seeking to make fun of anyone with its brand name, though it knew people would make the association with polygamy. He said the company would sue Idaho on principle if necessary.

"They shouldn't be able to ban a product based on its packaging without substantial reasoning," he said.

Turley has been involved in a lawsuit involving polygamy before. He represents the family of Kody Brown, a star of the reality TV show "Sister Wives," which follows Brown and his four wives. Brown, a former Utah resident, had sued in Utah, claiming the state's bigamy statute violates the family's constitutional rights.


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