...Legislators, the judiciary and the bar should... focus on the grand jury system in general, starting with the safeguards already in place to protect the system’s integrity and whether these safeguards are being used to their full potential.
For instance, one of the main criticisms of grand juries is that they’re puppets who simply do what prosecutors want them to do. Hence, the “myth” that grand juries would indict even a ham sandwich if asked to do so.
Yes, the prosecutor has control over what testimony and other evidence is presented to a grand jury. The prosecutor also instructs the grand jurors on the applicable law.
But if the grand jury does return an indictment, these closed door proceedings do get reviewed.
It’s standard procedure for the defense to make a motion challenging the sufficiency of the evidence before the grand jury. To rule on such a motion, a judge reviews the grand jury minutes in camera to determine whether there was sufficient evidence presented to support the charges or any improprieties during the presentation, such as misstatements of the applicable law.
If there were any defects in a grand jury presentation, the judge is in a position to address them, including dismissing the charges.