Within some criminal justice systems, a preliminary hearing (evidentiary hearing), often abbreviated verbally as a "prelim") is a proceeding, after a criminal complaint has been filed by the prosecutor, to determine whether, and to what extent, criminal charges and civil cause of actions will be heard (by a court), what evidence will be admitted, and what else must be done (before a case can proceed).
At such a hearing, the defendant may be assisted by counsel, indeed in many jurisdictions there is a right to counsel at the preliminary hearing. In the U.S.A., since it represents the initiation of "adversarial judicial proceedings", the indigent suspect's right to appointed counsel attaches at this point. See Moore v. Illinois, 434 U.S. 220, beginning at "The State candidly concedes that ..." (1977). Contrast this with some jurisdictions in the United States, where a person may be charged, instead, by seeking a "true bill of indictment" before a grand jury; where counsel is not normally permitted.
The conduct of the preliminary hearing as well as the specific rules regarding the admissibility of evidence vary from jurisdiction to jurisdiction. Should the court decide that there is probable cause, a formal charging instrument (called the Information) will issue; and the prosecution will continue. If the court should find that there is no probable cause, then typically the prosecution will cease. However, many jurisdictions allow the prosecution to seek a new preliminary hearing, or even seek a bill of indictment from a grand jury.
Some important questions, generally addressed in such a hearing, are:
If a judge determines that there is sufficient evidence to believe that the defendant committed the crime, it is said that the defendant is "held to answer".
After a defendant is held to answer, the judge will set a date for arraignment. A new pleading is filed with the court (sometimes called an "information") and the defendant can enter a plea at his or her arraignment date.