Arizona Revised Statutes Title 21. Juries § 21-402. Calling grand jury

A. In a county with a population of two hundred thousand persons or more a grand jury shall be called every four months each year by the presiding judge of the superior court. Each grand jury shall sit until a new grand jury has been impanelled to replace it or until its term expires pursuant to § 21-403. Additional grand juries shall be called on petition of the county attorney stating the reasons therefor.

B. In a county with a population of less than two hundred thousand persons the presiding judge of the superior court may call a grand jury either: