Grand jury decisions do not have to be unanimous. In the federal system, a grand jury may indict only if at least 12 jurors concur, and most states that use grand juries follow a similar supermajority rule rather than demanding a unanimous vote. So the short answer to whether grand jury decisions have to be unanimous is no — the law treats the indictment vote as a screening threshold, not a verdict.
The Federal 12-Vote Rule
Federal Rule of Criminal Procedure 6(f) sets the number plainly: “A grand jury may indict only if at least 12 jurors concur.”1Legal Information Institute. Federal Rules of Criminal Procedure Rule 6 – The Grand Jury A federal grand jury is made up of 16 to 23 people. That means the split can be as narrow as 12 to 11 and the indictment still stands. It is a fixed floor of 12 votes, not a percentage, and not a majority of whoever happens to be seated that day.
Put differently, a sizable minority of grand jurors can vote against charges and the prosecution still moves forward. The design is intentional. Because no one is being convicted at this stage, the rule treats the decision more like a filter than a final judgment.
Why the Bar Is Lower Than at Trial
The grand jury answers one narrow question: is there probable cause to believe a crime occurred and that this person committed it? Probable cause is a modest standard. The evidence must be strong enough that a reasonable person would conclude prosecution is warranted. It does not require proof, and it does not require certainty.2United States District Court Middle District of Florida. Handbook for Federal Grand Jurors
Trial juries operate on a different plane. A petit jury must find guilt beyond a reasonable doubt, the highest standard in criminal law, and criminal convictions almost always require a unanimous verdict. The grand jury’s role is smaller. It opens the door to a trial; it does not decide what happens on the other side. A supermajority fits the weight of what is actually being decided.
The one-sided nature of grand jury proceedings matters here too. The prosecutor presents evidence, calls witnesses, and explains the law. There is no judge, no defense attorney cross-examining, and typically no appearance by the person under investigation.3United States Department of Justice. Justice Manual 9-11.000 – Grand Jury Requiring every juror to agree based on only the prosecution’s version would set a strangely high bar for a preliminary step. The supermajority accounts for the reality that some jurors may hold reservations even when the evidence clearly supports moving ahead.
How State Grand Juries Vote
Federal rules bind federal proceedings, not state ones. The Fifth Amendment’s grand jury requirement for serious federal crimes was held in Hurtado v. California (1884) not to apply to the states.4Constitution Annotated. Amdt5.2.2 Grand Jury Clause Doctrine and Practice States set their own rules. Twenty-three require grand jury indictments for certain serious crimes, 25 make them optional, and two have abolished the grand jury for criminal indictments entirely.
Panel sizes and vote counts vary accordingly. Ohio seats nine grand jurors and requires seven to agree. Maine uses panels of 13 to 23 and always requires 12 votes. The federal threshold of 12 out of 16 to 23 sits in the middle of that range. What is consistent across almost every jurisdiction is that unanimity is not the standard.
True Bill, No Bill, and What Comes Next
After hearing the evidence, the grand jury votes. If the required number of jurors agrees that probable cause exists, the panel returns a “true bill” of indictment. The indictment is a formal document listing the charges and triggers the next phase of the criminal process. A defendant already in custody is typically arraigned within a few days. A defendant not in custody is usually arraigned within one to two weeks.
If the vote falls short, the grand jury returns a “no bill” and no indictment issues. A no bill is not an acquittal. The person under investigation has not been found innocent; the panel has simply decided the evidence was not strong enough to justify a trial at that point.
A no bill does not always end the matter. In the federal system, a prosecutor who wants to present the same case to another grand jury must first get approval from the responsible United States Attorney.3United States Department of Justice. Justice Manual 9-11.000 – Grand Jury There is no strict legal requirement that new evidence exist, though as a practical matter, running the same weak case past a new panel rarely changes the result. Some state rules are stricter and may require additional evidence before re-presentation.