( CNN ) -- A former Alabama university professor accused of gunning down three colleagues in February was indicted in Massachusetts on Wednesday in the 1986 shooting death of her brother . Amy Bishop was charged with first-degree murder in the killing of her brother , Seth Bishop , Norfolk District Attorney William Keating said . The brother 's death originally was ruled an accident . His death came under renewed scrutiny after Amy Bishop was arrested February 12 in a shooting rampage at a biology faculty meeting at the University of Alabama-Huntsville . At the time of the 1986 killing , Bishop , who was 21 , told authorities she had asked for her 18-year-old brother 's help unloading a shotgun when it accidentally discharged . Keating acknowledged Wednesday mistakes in handling the case , saying `` jobs were n't done , responsibilities were not met and justice was not served . '' `` Three individuals who were killed in Alabama may not have been '' had Bishop been charged in her brother 's death , Keating said . Bishop is awaiting trial in Alabama on capital murder and attempted murder charges in the university shooting . Three people were injured in the attack .
Seth Bishop 's shooting death originally was ruled an accident . Amy Bishop has also been charged with shooting university colleagues in February . District attorney acknowledges mistakes made in handling the 1986 killing .