The physician testified at a March 1 hearing that without treatment, L.K.'s cancer could kill her within three years. The physician said that L.K.'s "religious delusions" interfered with her ability to make reasoned decisions about her care, and that L.K. didn't understand that she might die without the surgery, according to the petition.

"L.K. then testified on her own behalf that she did understand that she had been diagnosed with cancer and that she did understand the risks of dying if she did not have the hysterectomy procedure," the petition said.

She also said that she might change her mind later about following her doctors' recommendations.

"L.K.'s dignity and bodily integrity are at stake and," the petition argued, " ... under the Montana Constitution her dignity is inviolable, including when her life or health is potentially at risk."

Such cases present thorny issues for legal experts and medical ethicists. Decisions turn on the degree of competence and the severity of the medical issue.

"The more a disease or a problem for an adult is life-threatening, the more likely it is that treatment is compelled if the person is mentally impaired," said Arthur L. Caplan, who heads the Center for Bioethics at the University of Pennsylvania.