Types of Juries

There are three types of juries in Arizona: State grand jury, county grand jury, and a trial or petit jury.  In Arizona jurors are chosen from the community where the courthouse is located, are over 18 years old, have not been previously convicted of a felony, and have not been diagnosed with a mental illness.  In all serious criminal cases, the defendant is entitled to a trial by a jury. This type of jury is a trial or petit jury, but there are also grand juries. Each serves a specific role in the judicial system.

Trial Jury or Petit Jury

In superior court, a trial jury for a criminal case consists of 8 to 12 persons, depending on the severity of the possible sentence. A unanimous verdict is required.

For superior court civil cases, there are eight people on the jury; the agreement of six members is required to return a verdict.

In limited jurisdiction courts, there are six-member juries. Unanimous agreement is required for a verdict in criminal cases, and five of the six jurors must agree on a verdict in civil cases.

The law does accept verdicts when fewer jurors agree if prior consent has been given by both the plaintiff and the defendant in a civil case. In a criminal case, the plaintiff, the defendant, and the court can determine the number of jurors required to be in agreement to return a verdict.

County Grand Jury

A grand jury is 12 to 16 citizens who have qualified for jury service in the county. Usually, they are called into session for a period of not more than 120 days.

A county grand jury is responsible for investigating possible public offenses, including corrupt or willful misconduct in office by public officials. To begin a criminal case, the county attorney may present evidence to a grand jury and ask it to return a criminal indictment or true bill, formally accusing someone of a crime.

An indictment means that a quorum (nine members) of the grand jury believe a crime has been committed and that there is enough evidence against the person to hold a trial.

State Grand Jury

The powers and duties of the state grand jury are similar to those of the county grand jury, except they extend statewide. Up to three grand juries can be assembled (impaneled) simultaneously at the state level. The scope of the investigations of a state grand jury is specified by law. The Supreme Court makes rules that govern the procedures of grand juries.