“The free exercise clause of the First Amendment protects religious belief,” the judge wrote in his ruling, “but not necessarily conduct.”

Wisconsin law, he noted, exempts a parent or guardian who treats a child with only prayer from being criminally charged with neglecting child welfare laws, but only “as long as a condition is not life threatening.” Kara’s parents, Judge Howard wrote, “were very well aware of her deteriorating medical condition.”

About 300 children have died in the United States in the last 25 years after medical care was withheld on religious grounds, said Rita Swan, executive director of Children’s Health Care Is a Legal Duty, a group based in Iowa that advocates punishment for parents who do not seek medical help when their children need it. Criminal codes in 30 states, including Wisconsin, provide some form of protection for practitioners of faith healing in cases of child neglect and other matters, protection that Ms. Swan’s group opposes.

Shawn Peters, the author of three books on religion and the law, including “When Prayer Fails: Faith Healing, Children and the Law” (Oxford, 2007), said the outcome of the Neumann case was likely to set an important precedent.

“The laws around the country are pretty unsettled,” said Mr. Peters, who teaches religion at the University of Wisconsin Oshkosh and has been consulted by prosecutors and defense lawyers in the case.

In the last year, two other sets of parents, both in Oregon, were criminally charged because they had not sought medical care for their children on the ground that to do so would have violated their belief in faith healing. One couple were charged with manslaughter in the death of their 15-month-old daughter, who died of pneumonia last March. The other couple were charged with criminally negligent homicide in the death of their 16-year-old son, who died from complications of a urinary tract infection that was severely painful and easily treatable.

“Many types of abuses of children are motivated by rigid belief systems,” including severe corporal punishment, said Ms. Swan, a former Christian Scientist whose 16-month-old son, Matthew, died after she postponed taking him to a hospital for treatment of what proved to be meningitis. “We learned the hard way.”

All states give social service authorities the right to go into homes and petition for the removal of children, Ms. Swan said, but cases involving medical care often go unnoticed until too late. Parents who believe in faith healing, she said, may feel threatened by religious authorities who oppose medical treatment. Recalling her own experience, she said, “we knew that once we went to the doctor, we’d be cut off from God.”

The crux of the Neumanns’ case, Mr. Peters said, will be whether the parents could have known the seriousness of their daughter’s condition.

Investigators said the Neumanns last took Kara to a doctor when she was 3. According to a police report, the girl had lost the strength to speak the day before she died. “Kara laid down and was unable to move her mouth,” the report said, “and merely made moaning noises and moved her eyes back and forth.”

The courts have ordered regular medical checks for the couple’s other three children, ages 13 to 16, and Judge Howard ordered all the parties in the case not to speak to members of the news media. Neither Ms. Falstad nor the defense lawyers, Gene Linehan and Jay Kronenwetter, would agree to be interviewed.

The Neumanns, who had operated a coffee shop, Monkey Mo’s, in this middle-class suburb in the North Woods, are known locally as followers of an online faith outreach group called Unleavened Bread Ministries, run by a preacher, David Eells. The site shares stories of faith healing and talks about the end of the world.

An essay on the site signed Pastor Bob states that the Bible calls for healing by faith alone. “Jesus never sent anyone to a doctor or a hospital,” the essay says. “Jesus offered healing by one means only! Healing was by faith.”

A link from the site, helptheneumanns.com, asserts that the couple is being persecuted and “charged with the crime of praying.” The site also allows people to contribute to a legal fund for the Neumanns.

In the small town of Weston, many people shake their heads with dismay when Kara Neumann is mentioned. Tammy Klemp, 41, who works behind the counter at a convenience store here, said she disagreed with the Neumanns’ passive response to their daughter’s illness but said she was not sure they should go to prison.

“I’ve got mixed feelings,” Ms. Klemp said. “It’s just such a terribly sad case.”

Chris Goebel, 30, a shipping department worker for a window maker, said many people in the area felt strongly that the parents should be punished.

“That little girl wasn’t old enough to make the decision about going to a doctor,” Mr. Goebel said. “And now, because some religious extremists went too far, she’s gone.”