A lawyer for an Ohio Amish family says forcing their daughter to get chemotherapy for her cancer violates their constitutional rights. Maurice Thompson argues that Anna and Andy Hershberger of Homer Township should be allowed to make the legal case against appointing a guardian for their daughter, the Medina Gazette reported. Thompson, executive director of the Libertarian 1851 Center for Constitutional Law, filed a brief with an Ohio appeals court Friday responding to arguments by the guardian, Maria Schimer, that the family waited too long to raise the argument that their religious freedom is being violated. "They have maintained all along that the government does not have the authority to do this," Thompson told the newspaper Monday. "A court shouldn't allow a mistaken ruling to stand that could affect every parent in the state." Sarah Hershberger was diagnosed with leukemia. The Medina County Probate Court ruled last year that her parents could not be compelled to consent to chemotherapy, but an appeals court ordered a guardian at the request of Akron Children's Hospital, which said Sarah, 10, would die within a year without treatment. The family left their home last year, and friends said they had left the country looking for an alternative treatment. Schimer has submitted her resignation as guardian, but a court has not given its approval. Her attorney says the hospital had  not seen the girl and had no idea of her whereabouts.