We’ve all heard of grand juries but few probably understand what the actual difference is between a normal jury and a grand jury and what their function is. If you are interested in understanding, here is an overview.
The first main difference between the two is size. Regular (or petit) juries usually have about 6 to 12 people, but a grand jury is can be anywhere from 12 to 23 people.
Another main difference is serving time. Unless one is sequestered or involved in a complex case, most petit cases only last a couple days at most and then you have fulfilled your duty. For a grand jury, however, it is a much larger time commitment. If you are selected for a grand jury, you are required to stay on from anywhere of a few months to up to a year. Typically you would only be called in a few days a week but it can most definitely have significant impacts on your life.
Both juries tend to be used very differently. A petit jury is there to hear a trial case and decide whether the prosecution has proved guilt beyond a reasonable doubt. With that, a judge will decide a sentence and that will conclude the trial. With a grand jury, the purpose is not that of a trial where a sentence would be handed out, but one where the jury hears evidence and helps decide whether prosecutors should pursue criminal charges in the first place.
In a petit trial, you are there for one case. You will hear from all sides and when the jury decides a verdict, the trial concludes. That will be the end of the juror’s duty. With a grand jury, you will actually sit for many cases, even several a day. Since the job is not to convict but simply decide whether the prosecutors should indict, there tends to be more cases to deliberate on.