I wouldn’t necessarily call it a scape goat. It’s intended to bring a level of impartiality which I think is a good thing. I’m general I think they should be used more often , but especially in cases where it can be high profile.

A case this high profile not even a grand jury would function as a scapegoat. If they got the indictment but not the conviction because they overplayed the evidence they had…let’s just say it would not be a positive career move. They absolutely want the opinion of the grand jury on the evidence they have and playing fast and loose with bias to get the indictment with weak evidence would be self-destructive.