A prosecutor filed criminal charges on Thursday against Pennsylvania’s attorney general, Kathleen G. Kane, in a convoluted tale of political maneuvering and retribution that threatens the career of an official who, until recently, was seen as one of her state’s rising stars. Ms. Kane, a Democrat in her first term, has been accused of illegally giving grand jury documents to a newspaper in order to embarrass a critic, and then trying to cover up her actions with false testimony to a different grand jury. The Montgomery County district attorney, Risa V. Ferman, charged the attorney general with counts that include...