What Does a Grand Jury Do?

Grand juries play a gatekeeping role in the criminal system. They decide whether a case should go forward, not whether the accused is guilty.

Grand jury vs. trial jury

Federal numbers come from Rule 6 of the Federal Rules of Criminal Procedure.

When a grand jury is required

The Fifth Amendment requires a grand jury indictment for serious federal crimes. States are not required to use grand juries; about half use them for some felonies, while others start felony cases with a preliminary hearing before a judge (Cornell LII).

How it works

1. The prosecutor presents evidence and witnesses.
2. Jurors can ask questions.
3. The defense usually does not present a case, and the accused has no right to appear.
4. Jurors vote. If enough agree, they return a true bill (indictment). If not, a no bill.

Secrecy

Grand jurors, prosecutors and court staff must keep proceedings secret (Rule 6(e)). Witnesses in federal cases are generally free to discuss their own testimony.

If you receive a grand jury subpoena

• It is a court order; ignoring it can lead to contempt.
• You may be a witness, a "subject" whose conduct is being examined, or a "target" likely to be charged. Federal prosecutors often send a target letter.
• In federal grand juries, a witness's lawyer cannot be in the room, but you can step out to consult.
• You can invoke the Fifth Amendment privilege against self-incrimination.

Talk to a lawyer before testifying. See also what to do if you are subpoenaed.

Grand jury duty

If you are summoned to serve, service can last weeks or months, meeting periodically. Information is in your summons and on the court's jury website (US Courts).

If you learn you are a target or subject, contact a criminal defense lawyer right away.

Sources

1. Cornell Law School LII: Grand jury
2. Cornell Law School LII: Federal Rules of Criminal Procedure, Rule 6
3. Cornell Law School LII: Fifth Amendment
4. United States Courts: Jury service