It depends. Virtually all federal cases proceed by a grand jury indictment. In Nevada state court, the majority of cases do not involve a grand jury at all. But prosecutors often decide to utilize a grand jury in particularly serious or high-profile cases.
Grand jury proceedings are secret hearings that come into play at the beginning of a criminal case in Nevada. During a grand jury proceeding, the prosecution presents evidence to a pool of 16 to 20 people about an alleged crime. Unlike trial juries which determine a defendant's guilt or innocence, grand juries merely evaluate whether sufficient evidence exists to charge the suspect with a crime. If the grand jury believes there is sufficient evidence, the defendant will be "indicted" (charged) with the alleged crimes.
Defendants are allowed testify to their own innocence at grand jury proceedings in Nevada. However, it is recommended that defendants remain silent. Defense counsel are not allowed at grand jury proceedings, and defendants risk saying something incriminating on the stand that can be used against them later. Read more information on Nevada grand juries. For more information about the criminal process, see our article, "Five Things to Know When You Are Arrested in Nevada."