A woman sentenced to death when she was a teen for a 1995 murder in Knoxville is asking that her death sentence be vacated, citing recent rulings that factored youth and mental illness or brain damage into sentencing. Christa Gail Pike and two others were convicted in the brutal murder of 19-year-old Colleen Slemmer when all four teens were participating in Job Corps, a federal jobs training program for troubled adolescents, in Knoxville.