|Function of the grand jury|
A grand jury is a type of jury that determines whether a criminal indictment will be issued. Currently, only the United States retains grand juries, although some other common law jurisdictions formerly employed them, and most other jurisdictions employ some other type of preliminary hearing. In Ireland, they also functioned as local government authorities.
A grand jury is so named because it has a greater number of jurors than a trial jury (also known as a petit jury, from the French for small).