The reason why there was a grand jury for Ferguson was that the DA did not want to be accused of favoratism toward the cop.
That’s cool.
I support grand juries. probable cause is not a high threshold at all.
Now we have a case were it looks like the state attorney is favoring a street mob.
Follow on question: If a grand jury is optional for an indictment why have one? (Often wondered about the grand jury system and why it was needed.)