California's attorney general asked a court on Tuesday to bar Michael Jackson's former doctor, Conrad Murray, from practicing medicine while he faces charges in connection with the pop star's death. Jerry Brown filed a petition in Los Angeles Superior Court on behalf of the California Medical Board asking that a judge restrict the medical license of Murray, who faces involuntary manslaughter charges, as a condition of his bail. Last month, a judge rejected a request by Los Angeles prosecutors to suspend Murray's license but ordered him not to use anesthesia on his patients. Brown, a former California governor who announced on March 2 he would seek the Democratic nomination for the governorship, has waged a campaign against doctors who over-prescribe drugs. Among the cases his office has investigated are the February 2007 death of Anna Nicole Smith, 39, of a prescription drug overdose. Brown has said his office will also investigate the March 12 death of 38-year-old actor Corey Haim, apparently of a prescription drug overdose.