Didn't change the law in the direction they wanted, and didn't achieve justice either.
Also, one "short coming" of jury nullification is that it doesn't actually nullify the law, just the outcome of individual trials which, yes, can be abused as it was in the South. The precedent it can create, if enough juries nullify similar trials, is reducing over zealous prosecution and prosecutors. So, when a true RICO case comes up the law can appropriately be used. But when RICO is used in a case just to trump up charges, prosecutors will be less apt to pursue if its going to hurt their record of convictions and careers.