A Grand Jury is a legal body that is empowered to conduct official proceedings to investigate whether potential criminal Conduct warrants criminal charges. A Grand Jury is considered sepearte from the courts and courts do not preside over its functioning. A Grandy Jury may compel or order the production of documents and may compel the sworn testimony of witnesses to appear before it.

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1) A Grand Jury is usually comprised of 12-23 citizens.
2) The United States is virtually the only country that retains or uses Grand Juries. Some places simply use some other preliminary hearing in place of a Grand Jury.