washington d.c. approved the first charges in the investigation being led by mueller. tell us about the work of a grand jury and what it means to say a grand jury has approved charges. >> typically what happens in a grand jury investigation they hear evidence, where it can be one day in a little case or a big dais case like this where they hear testimony and see exhibits over a matter of months. and at some point the prosecutor makes a decision to seek or decline to seek an indictment. they think they've gotten to the place where they have probable cause to go forward. so they draft an indictment, present it to the grand jury, discuss the law and the elements of the offenses, answer any questions they have, and leave the room. leave the grand jury to deliberate among themselves and make a decision whether they prove or decline to approve -- they call it issuing a true bill or issuing a no true bill. it sounds like they issued a