Rule 3.1 - Issuance of Summons or Warrant(a)Issuance. A summons commands a defendant to appear before a magistrate. A warrant commands the arrest of a defendant by a peace officer for the purpose of bringing a defendant before a magistrate. (1)Return of Indictment. If a grand jury returns an indictment, the court must promptly issue a warrant or summons, or a notice of supervening indictment under Rule 12.6(c).(2)Finding of Probable Cause. If a magistrate makes a finding of probable cause under Rule 2.4(a), the court must promptly issue a warrant or summons.(3)Prosecutor's Complaint. If a prosecutor presents a signed complaint, the court must promptly issue a summons or, if the court finds probable cause, the court may issue a warrant.(b)Preference for Summons. Unless there is good cause to issue a warrant, a court should issue a summons if the defendant is not in custody, the offense charged is bailable as a matter of right, and there is reason to believe that the defendant will appear. If a prosecutor requests a warrant, the prosecutor must state the reasons for issuing a warrant rather than a summons.(c)Initial Arrest Warrant. Before issuing a warrant, the magistrate must determine that probable cause exists that the defendant committed the offense or find that such a determination was previously made. The court may issue an initial arrest warrant if:(1) a defendant failed to appear after being served with a summons;(2) there is good cause to believe that the defendant will not appear; or(3) a summons cannot readily be served or delivered.(d)Pre-Disposition Warrant. After the initial appearance and before the disposition of a case, the court may issue a warrant to secure a defendant's appearance if the defendant fails to appear after receiving proper notice.(e)Warrants in Criminal ATTC Cases. If a person served with an Arizona Traffic Ticket and Complaint provides a written promise to appear in court at a designated time and date and fails to appear, personally or by counsel, on or before that date, the court may issue a warrant. If a complaint is filed under A.R.S. § 13-3903(F), the court must issue a warrant for that proceeding.Added August 31, 2017, effective 1/1/2018.