MADISON, Wis. — In 1992, Robert O. Barton was charged with having sexual intercourse with a 4-year-old child in Wausau. The child told authorities she was sexually assaulted at least 10 times, according to the disturbingly graphic court documents. Barton, 41 at the time, was charged with first-degree sexual assault of someone under the age of 13, and child enticement, sexual contact. He faced a maximum prison sentence of 70 years on the two counts. Two Wausau police officers testified to the validity of the child’s accusations. But the charges eventually were dismissed by Marathon County Judge Ann Walsh Bradley,...