Holder will still have to convince a St Louise grand jury to indict on civil rights violations. More than likely the Justice Dept will send monitors to Ferguson PD (Like Sheriff Joe Arpio’s office in Phoenix, and study it, going back years, to see if there is a pattern of profiling or discrimination, then they will charge them criminally or civilly. Can crush a locality. The full force of the government is a violent thing.
What makes you think the federal grand jury will be in St. Louis?