NASHVILLE, Tenn. (AP) — Tennessee officials have been unable to put Christa Gail Pike to death for a 1995 murder after administering two doses of a lethal drug. A death penalty expert said it was an unprecedented failure. Tennessee Gov. Bill Lee late Wednesday halted the remaining scheduled execution for the rest of the year and ordered an outside investigation. Pike’s attorneys say she was alive and loudly snoring after the attempted lethal injection and taken by ambulance from the prison. Her attorneys said in court filings that officials gave Pike two doses of pentobarbital. The Tennessee Department of Correction says they followed every step of the state’s execution protocol.