With the conviction of polygamist sect leader Warren S. Jeffs, an eight-member jury in Utah's Washington County sent a powerful message to religious groups: Make sure your religious practices aren't in conflict with civil law.

Being a fundamentalist is no excuse for tolerating or promoting practices that harm or sexually exploit children. Considered a prophet by his 10,000 followers in the Fundamentalist Church of Jesus Christ of Latter Day Saints, Mr. Jeffs was convicted of being an accomplice to the rape of a 14-year-old girl.

As Mr. Jeffs' lawyers tirelessly pointed out during his trial, he was not in the room when the rape occurred. Still, Mr. Jeffs was convicted of sanctioning the 14-year-old's marriage to her much older first cousin.

The woman, now 21, told the jury through tears about the sexual trauma of her forced marriage to a man she didn't love. It was within Mr. Jeffs' power as the religious authority and head of his polygamist sect to release the young woman from her betrothal. She insisted she was not physically or emotionally mature enough for marriage at the time. Instead of releasing her from her "obligation," Mr. Jeffs counseled her to be sexually submissive to her husband. In his capacity as a religious leader, the defendant acted more like a pimp than a moral arbiter.

America has tolerated many expressions of faith over many centuries. Polygamy is still practiced in tiny pockets around the country, usually by Mormon fundamentalists.

The conviction of Warren Jeffs puts religious communities on the fringe on notice. Illegal and immoral practices will not be tolerated because they believe God sanctions their behavior, especially when they involve children. After the trial, the ex-husband at the center of the case, Allen Glade Steed, 26, was charged with rape.

Whatever time Mr. Jeffs is sentenced to spend behind bars may not be enough for the loss of one young woman's childhood. Any leader who sacrifices children on an altar erected by dirty old men should look only to God for mercy, not the courts.