until now, siobhan o'connor had carefully kept her identity secret. >> siobhan o'connor: i had to relyver have before. >> whitaker: she is the whistlebwer whakedecds ch asve ofese buffa wked closeo his executive assistant for three years. last week, she spoke with the f.b.i. some people would say that you betrayed bishop malone. >> o'connor: i did betray him, and yet i can't apologize for that, because there was a greater good to consider. >> whitaker: the hundreds of pages siobhan o'connor uncovered included personnel files and memos. they revealed that for years, bishop malone allowed priests accused of sexual assault, such as statutory rape and groping, to stay on the job. >> o'connor: i love my church, i love our diocese, and i-- i loved him. i-- i genuinely did, as my bishop and as my boss. >> whitaker: so why are you doing this? >> o'connor: the reality of what i saw really left me with no other option because, at the end of my life, i'm not going to answer to bishop malone. i'm going to answer to god. >> whitaker: at first, she took pictures with her phone. then, she used the co