Though the grand jury is an important piece of the criminal justice system, it doesn’t determine guilt or impose penalties. Instead, a prosecutor convenes a grand jury to determine whether to indict – bring charges against – a person suspected of committing a crime.

Though all states have provisions for grand juries, only about half make use of them. In Minnesota, a grand jury can include up to 23 people, though they can function with as few as 16.

The state says a grand jury must be convened in cases in which “the offense charged is punishable by life imprisonment” and that prosecutors have the option to use grand juries in other cases.

Grand juries hear one side

One of the important differences between a grand jury and a trial jury is that a grand jury hears from only one side – the prosecutor.

Criminal defense attorneys are not directly part of the grand jury process, though it’s important for suspects to get legal counsel.

Prosecutors can also subpoena witnesses, “who have to testify under oath” to the jurors, the state says.

Presentation of evidence

In these proceedings, the prosecutor presents evidence to the grand jury “to establish there is probable cause to believe an offense has been committed and the defendant committed it,” the Minnesota Judicial Branch says on the state website.

Witness testimony consists of answering questions posed by the prosecutor – and by jurors.

In often complex white-collar cases involving allegations of tax fraud, healthcare fraud, wire fraud or related crimes, it’s important to have legal representation even if you’re not the focus of the proceeding. The focus can shift as a result of information given to the grand jury.

Attorneys for grand jury witnesses

Attorneys for witnesses are one of the few people allowed to be present in grand jury proceedings, in addition to the prosecutor and jurors. Attorneys can advise and consult with a witness during testimony, if the witness has waived the privilege against self-incrimination or has been granted immunity.

After the grand jury’s heard the evidence, jurors vote on the indictments presented by the prosecutor. If at least 12 jurors vote that evidence establishes probable cause, an indictment is issued.

It’s known as a “no bill” when no indictment is issued.

The secrecy of grand juries

The state demands grand jury secrecy – transcripts aren’t made public and jurors aren’t allowed to talk about the proceedings. Why so secretive? Secrecy’s intended to encourage witnesses to speak freely and to protect the reputations of those people who are not indicted.

Another element of the secrecy is that witnesses testify to the jury one at a time. In that way, witnesses cannot hear other testimony or questions.

It should be noted that a case is not necessarily over just because no indictment is issued. A case can go back to a grand jury, if a judge allows it.