A grand jury is a group of individuals chosen to review evidence a prosecutor presents and decide whether or not an indictment, which is a formal charge, is in order. This procedure is typically followed for very serious criminal cases. In the United States, grand juries may convene for national cases or to handle state legal matters. A state grand jury is a grand jury assembled by a state court system.
Like those that are convened by a federal court, state grand juries have the job of determining whether there is probable cause for indicting an individual or group of individuals. This differs from trial juries, which typically have the job of deciding whether or not an individual is guilty of a crime. Grand juries listen to testimony and decide whether or not a person should be charged in the first place. A grand jury may also review evidence as part of investigating whether or not a crime has been committed and deciding whom should be charged with that crime.
In the United States, every state court system may use grand juries, though some may not convene them regularly. There are other countries that use grand juries as well. They are not referred to as state grand juries, however, unless the country has subdivisions that are referred to as states and these subdivisions have court systems that use grand juries.
Often, the size of a state grand jury differs from that of a national grand jury. In the United States, for example, a grand jury is usually made up of at least 16 people, but not more than 23. The size of a state grand jury typically depends on the state. For example, one state may convene grand juries that include 16 jurors while another may require 18 jurors. Some specify a range, such as between 12 and 16 jurors, while others may allow for a couple of different jury sizes, such as 11 or 19.
Usually, a state grand jury doesn’t meet every day. This differs from a trial jury that may meet each day until it has reached its verdict. Sometimes state grand juries may meet only once per week, every other week, or even once a month. In some cases, a state grand jury will only convene occasionally. For example, it may only convene when a state prosecutor has a case he wants to put before it.
Interestingly, the frequency with which a state grand jury is convened doesn't determine how long a juror might serve the court system. The term he serves depends on the state in question. A juror in one state may serve for just one month while another state may require its jurors to serve for an entire year.