The Difference Between a Grand Jury and a Preliminary Hearing

Probable cause is determined in a preliminary hearing or through a grand jury.

The Difference Between a Grand Jury and a Preliminary Hearing

In our justice system, when a person is charged with a felony, they cannot be immediately sent to trial after being charged. Instead, the prosecution has to prove there was “probable cause” that a crime was committed and, if so, that the defendant was actually the person who committed the crime.

In Arizona, this can be accomplished through either a preliminary hearing or a grand jury indictment.

In a preliminary hearing, the prosecutor, defendant, and defense attorney present their evidence in court to a judge. This evidence can include reliable hearsay and witness testimony, which the Defense is able to question. Preliminary hearings are public record. Ultimately, the judge makes the determination as to whether there is sufficient evidence and probable cause that the defendant committed the alleged crime. In this situation, the case will be moved to Superior Court for further hearings like arraignment, pretrial conference, change of plea or trial. If the judge does not find probable cause, the prosecutor can choose to present in front of a grand jury or file a new complaint with new evidence or charges.

On the other hand, grand jury proceedings are held secretly to protect both the defendant and the witnesses, and the defendant, their attorney, and the judge are not in attendance for this proceeding. With that being said, there is case law in Arizona that allows a defendant to request in writing to be made available for an accused to be called to testify before the grand jury. Grand jury records are not made public. A jury of peers of at least nine individuals is randomly selected to serve on the grand jury. This jury then hears all the evidence presented by the prosecutor. The grand jury can choose to allow the defendant to testify, and they can also request additional witnesses to be called. If a majority of jurors believe there is probable cause, they will issue a “True Bill” of indictment, setting the case for trial. If the grand jury does not return a true bill, the defendant will be released without charges, although the prosecutor can file a new criminal complaint to present at a preliminary hearing.

It is more common for criminal complaints to be sent to a grand jury rather than go through a preliminary hearing in Arizona, as grand juries allow for the uncontested presentation of evidence from the prosecution.



With offices in Lake Havasu City and Scottsdale, our firm serves the entire state of Arizona, with a particular focus on criminal defense, family law, and juvenile cases.

Our goal is for the best outcome for your criminal case, which can include:

  • charges that are reduced or dropped.
  • top experts reviewing your case.
  • aggressive negotiations with the prosecution for plea bargains.
  • fines or probation in lieu of jail time.

At Rideout Law Group, our attorneys are able to expertly examine the evidence in your case to provide a strong strategy for argument that leads to an outcome that is most favorable to you. We have experience in all types of criminal cases for both adults and juveniles, with positive outcomes both in plea negotiations as well as jury trial settings.

Call us today for a free consultation at 480-584-3328.

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