Kody Brown and his wives Meri, Janelle and Christine, along with Robyn, are the subject of a TLC program called "Sister Wives."

SALT LAKE CITY — Utah Attorney General Mark Shurtleff wants a federal judge to dismiss a polygamous family's lawsuit challenging the state's bigamy law, contending the stars of "Sister Wives" lack standing to do so.

Kody Brown and his four wives have failed to show that their constitutional rights were violated as a result of the statute, according to a motion filed in U.S. District Court.

"The Brown family is hardly the only polygamist family in Utah," the 15-page memorandum says, noting there are about 30,000 polygamists in the state. "There are not 30,000 cases currently being prosecuted in Utah — there is not even one."

Utah County Attorney Jeff Buhman has threatened to file charges against the Browns since their television reality show "Sister Wives" debuted last September. And their lawyer, Jonathan Turley, said that alone is enough to put the family in a position to sue the state over the bigamy law.

In filing the suit against the state and county last month, Turley said the Browns, who moved to Nevada in January, are not demanding recognition of their polygamous marriage. The lawsuit questions the right of the state to prosecute people for their private relations and demands equal treatment with those living according to the beliefs.

Turley called the state's motion an effort to avoid scrutiny of a "facially unconstitutional" law.

"Under this extreme position, state officials can criminalize any private relationship while denying the right of citizens to challenge the law, even when those citizens are denounced as presumptive felons by prosecutors in the media," he said. "We will vigorously oppose the effort to close the door of the courthouse to this family."

In a declaration filed along with the attorney general's motion, Buhman wrote that he has not "publicly stated" whether he will prosecute, an indication that perhaps he has made up his mind.

Filing charges now might actually weaken the state's defense because it could lend credence to the Brown's contention that the bigamy law has limited their rights.

University of Utah law professor Paul Cassell said prosecuting the Browns now would create a "live" question about whether the law is constitutional. Federal courts are reticent to take on cases that aren't "ripe" or that lack controversy. Charges could change the tenor of the issue.

Assistant attorney general Jerrold Jensen argues in the memorandum that the Browns have not shown even a "credible threat" of prosecution because the attorney general's office does not go after polygamists unless it suspects other crimes such as child abuse. Although Utah County does not have such a policy, its track record "belies any likely prosecution."

No one in the county attorney's office could recall prosecuting anyone for polygamy, Buhman wrote.

Only three Utah polygamists since 1960 have been prosecuted under the bigamy law but only in conjunction with other crimes, according to the state's memorandum.

Court documents say the Browns were open about their polygamous lifestyle before their reality show aired and were well known to both state and county officials.

"Now, however, plaintiffs claim that because they became the subject of 'Sister Wives' and the Lehi city police reported that to the Utah County Attorney's Office that they are  now somehow the target of prosecution," the memorandum states.

Buhman's declaration said little was revealed in the police report that was not made public in the TV show's first episode last September.

The second season of "Sister Wives" is set to begin later this month on TLC. The program chronicles the lives of Kody Brown and his wives Meri, Janelle, Christine and Robyn and their 16 (soon to be 17) children.

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