The court — with the chief justice dissenting — said Tuesday that religious protections of the U.S. and Utah constitutions "do not shield (Rodney) Holm's polygamous practices from state prosecution."
Holm was convicted of felony bigamy and two counts of unlawful sexual conduct with a minor, and had argued that the state's bigamy statute violated his right to practice his religion.
County prosecutors began an investigation after one of Holm's "spiritual" wives left the faith and sued him over the custody of their two children. The woman said she married Holm in a 1988 religious ceremony when he was 32 and she was 16. At the time, Holm already was legally married to the woman's sister and claimed another "spiritual wife."
The former Hildale police officer was sentenced to a year in jail and is now on court-supervised probation.
Chief Justice Christine Durham issued a dissenting opinion saying Holm's bigamy conviction should not be upheld.
She said that applying the bigamy law to marriages solemnized only in religious ceremonies "oversteps lines protecting the free exercise of religion and the privacy of intimate, personal relationships between consenting adults."
Holm and the women were members of the Fundamentalist Church of Jesus Christ of Latter Day Saints, a polygamist sect based in Hildale, Utah, and Colorado City, Arizona.
The sect split from mainstream Mormonism after the broader church renounced polygamy in 1890. The mainstream LDS church excommunicates members found to be practicing polygamy.
Earlier this month the FBI placed the fugitive leader of the Fundamentalist Church of Jesus Christ of Latter Day Saints on the agency's Ten Most Wanted list with a $100,000 reward.
Warren Jeffs is accused of arranging marriages between underage girls and older men. He is charged with child sexual abuse in Arizona and being an accomplice to statutory rape in Utah.