sit could tall come down to this. >> reporter: it could. if you haven't been watching this crowd. there is two people you need to know about beef sides dr. murray and michael jackson. dr. steven shaffer was the star witness for the prosecution. he says dr. murray is responsible. his good friend, his colleague for 30 years, a guy who is considered an test teamed expert in propofol and someone who says dr. murray could not have don't is dr. paul white and he's the star witness for the defense. the two experts in the world on propofol are testifying against each other. so now we are in the courtroom. dr. white has been on the stand. it started yesterday mid-day. he's been take apart what dr. shaffer said last week. >> i thought there were questions if in fact murray had