In the early decades of the United States grand juries played a major
role in public matters. During that period counties followed the
traditional practice of requiring all decisions be made by at least
twelve of the grand jurors, (e.g., for a twenty-three-person grand
jury, twelve people would constitute a bare majority).
Any citizen could bring a matter before a grand jury directly, from a
public work that needed repair, to the delinquent conduct of a public
official, to a complaint of a crime, and grand juries could conduct
their own investigations. In that era most criminal prosecutions were
conducted by private parties, either a law enforcement officer, a
lawyer hired by a crime victim or their family, or even by laymen. A
layman could bring a bill of indictment to the grand jury; if the
grand jury found there was sufficient evidence for a trial, that the
act was a crime under law, and that the court had jurisdiction, it
would return the indictment to the complainant.
The grand jury would then appoint the complaining party to exercise
the authority of an attorney general, that is, one having a general
power of attorney to represent the state in the case. The grand jury
served to screen out incompetent or malicious prosecutions. The advent
of official public prosecutors in the later decades of the 19th
century largely displaced private prosecutions.
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Grand juries were popular in the Eastern states because in the Revolutionary War period and the period leading up to the Revolutionary War in the United States, grand juries were used as a tool of resistance to what was perceived as oppressive British rule by citizens of the American colonies.
But, that fervor had faded and the difficulty of finding grand jurors on the frontier discouraged the use of this institution of people migrated to the west to form new states, and as the prosecution of crimes came to be the sole or predominant province of professional prosecutors employed by the state.
