The family with four wives had hoped its participation on a TLC reality TV show would shed light on polygamy but is now the target of a bigamy investigation by Utah police.

"Sister Wives," which premiered Sunday, chronicles the life of 41-year-old advertising salesman Kody Brown, his four wives, 13 children and three stepchildren. The Browns, of Lehi, have said they hoped that the peek into their lives would help broaden the public's understanding of plural families.

Lehi police are investigating whether the family is violating bigamy laws in plain view on cable TV. Brown is only legally married to Meri but also calls three other women his spouses: Janelle, Christine and Robyn.

"...When we decided to do this show, we knew there would be risks," the Brown family said in a statement Tuesday. "But for the sake of our family, and most importantly, our kids, we felt it was a risk worth taking."

Most polygamist families practice in secret, but it has entered the national dialogue given its portrayal on the HBO scripted drama "Big Love." The modern Mormon church excommunicates members found engaged in the practice, which was disavowed by the church in 1890 as part of a push for Utah's statehood.

On a TLC ad for "Sister Wives," one wife says: "I think we're normal, and then I go out and then I'm like, 'Oh yeah, I can't tell anybody about my normal family.'"

Across Utah and parts of the western U.S., an estimated 38,000 self-described fundamentalist Mormons continue to believe and/or practice polygamy, believing it brings exaltation in heaven.

Over the past 10 years, Utah's historically insular polygamist community has worked to educate the public and state agencies about its culture. State agencies now better understand the unique aspects of polygamous culture and plural families are less hesitant to seek help when needed, Principle Voices co-founder Anne Wilde said.

The Brown family's decision to do a reality TV show was sort an extension of that education work, said Wilde, who knows the family well.

Although it is rarely prosecuted, bigamy is a third-degree felony in Utah, punishable by a prison term of up to five years. Under the Utah law, a person can be found guilty of bigamy through cohabitation, not just legal marriage contracts.

Lehi police said the evidence gathered from the probe will be turned over to the Utah County attorney's office for possible prosecution. A message left for Paul was not immediately returned Tuesday.

Utah last prosecuted a polygamist for bigamy in 2001. Tom Green, who was married to five women and drew the attention of Utah authorities after promoting his lifestyle on national TV talk shows, was convicted on bigamy, criminal nonsupport and child rape charges. He spent six years in prison and was released in 2007.

The Utah attorney general's office has investigated the state's secretive polygamous communities, but focused its efforts on cases involving allegations of abuse, sexual assault and fraud, not bigamy.

"It has been our office's position not to pursue cases of bigamy between consenting adults," the attorney general's spokesman, Scott Troxel, said Tuesday. "We want to use our resources wisely."

Wilde said she fears an investigation into the Brown family will instill fear in plural families about going public with their lives.

"If it really goes to a court situation, then our people are going to go right back into isolation," she said.